Page 1
R&S® ZVA
Vector Network Analyzers
Getting Started
(;]:èÌ)
1145.1090.62 ─ 13
Getting Started
Test & Measurement
Page 2
This Getting Started guide describes the following vector network analyzer types:
●
R&S® ZVA8, order no. 1145.1110.08/10 (2 or 4 test ports)
●
R&S® ZVA24, order no. 1145.1110.24/26 (2 or 4 test ports, 2 generators)
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R&S® ZVA24, order no. 1145.1110.28 (4 test ports, 4 generators)
●
R&S® ZVA40, order no. 1145.1110.40/42 (2.92 mm, 2 or 4 test ports, 2 generators)
●
R&S® ZVA40, order no. 1145.1110.48 (2.92 mm, 4 test ports, 4 generators)
●
R&S® ZVA40, order no. 1145.1110.43/45 (2.4 mm, 2 or 4 test ports, 2 generators)
●
R&S® ZVA50, order no. 1145.1110.50/52 (2 or 4 test ports)
●
R&S® ZVA67, order no. 1305.7002.02/04 (2 or 4 test ports)
●
R&S® ZVA80, order no. 1312.6750.02/03/04. An additional Getting Started guide 1312.6808.62 is
available for these instruments.
●
R&S® ZVA110, order no. 1312.7004.03/04. An additional Getting Started guide 1314.4502.62 is available for these instruments.
The firmware of the instrument makes use of several valuable open source software packages. For information, see the "Open
Source Acknowledgement" on the user documentation CD-ROM (included in delivery).
Rohde & Schwarz would like to thank the open source community for their valuable contribution to embedded computing.
© 2015 Rohde & Schwarz GmbH & Co. KG
Mühldorfstr. 15, 81671 München, Germany
Phone: +49 89 41 29 - 0
Fax: +49 89 41 29 12 164
E-mail: info@rohde-schwarz.com
Internet: www.rohde-schwarz.com
Subject to change – Data without tolerance limits is not binding.
R&S® is a registered trademark of Rohde & Schwarz GmbH & Co. KG.
Trade names are trademarks of the owners.
The following abbreviations are used throughout this guide: R&S® ZVAxx is abbreviated as R&S ZVAxx, R&S® ZVA-xxx as R&S
ZVA-xxx
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R&S® ZVA
Contents
Contents
1 Preparing the Analyzer for Use.............................................................7
1.1 Front Panel Tour........................................................................................................... 7
1.1.1 Display............................................................................................................................ 8
1.1.2 Setup Keys......................................................................................................................9
1.1.3 Navigation Keys............................................................................................................ 10
1.1.4 Data Entry Keys............................................................................................................ 11
1.1.5 Rotary Knob.................................................................................................................. 12
1.1.6 Standby Key..................................................................................................................12
1.1.7 Front Panel Connectors................................................................................................ 12
1.1.8 Additional Hardware Options........................................................................................ 15
1.2 Rear Panel Tour...........................................................................................................15
1.3 Putting the Analyzer into Operation..........................................................................17
1.3.1 Unpacking and Checking the Analyzer......................................................................... 18
1.3.2 Setting up the Analyzer................................................................................................. 18
1.3.3 Bench Top Operation.................................................................................................... 19
1.3.4 Operation in a 19" Rack................................................................................................ 20
1.3.5 EMI Suppression...........................................................................................................20
1.3.6 Connecting the Analyzer to the AC Supply................................................................... 21
1.3.7 Power on and off........................................................................................................... 21
1.3.8 Standby and Ready State............................................................................................. 21
1.3.9 Replacing Fuses........................................................................................................... 22
1.4 Starting the Analyzer and Shutting Down.................................................................22
1.5 Windows Operating System.......................................................................................23
1.6 Connecting External Accessories............................................................................. 24
1.7 Connecting to a LAN...................................................................................................25
1.7.1 Physical LAN Connection..............................................................................................25
1.7.2 TCP/IP Configutation.................................................................................................... 25
1.7.3 Test Setups with two LAN Connections........................................................................ 27
1.8 Remote Desktop Connection..................................................................................... 28
1.9 Firmware Update......................................................................................................... 29
2 Getting Started..................................................................................... 30
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R&S® ZVA
Contents
2.1 Performing a Reflection Measurement..................................................................... 30
2.1.1 Instrument Setup for Reflection Measurements............................................................31
2.1.2 Parameter and Sweep Range Selection....................................................................... 32
2.1.3 Instrument Calibration .................................................................................................. 33
2.1.4 Evaluation of Data ........................................................................................................35
2.1.5 Saving and Printing Data ............................................................................................. 36
2.2 Performing a Transmission Measurement............................................................... 37
2.3 Basic Tasks................................................................................................................. 37
2.3.1 Control via Front Panel Keys........................................................................................ 37
2.3.2 Data Entry..................................................................................................................... 39
2.3.3 Scaling Diagrams.......................................................................................................... 41
3 System Overview................................................................................. 45
3.1 Basic Concepts........................................................................................................... 45
3.1.1 Global Resources..........................................................................................................45
3.1.2 Setups........................................................................................................................... 46
3.1.3 Traces, Channels and Diagram Areas.......................................................................... 46
3.1.4 Data Flow...................................................................................................................... 48
3.2 Screen Elements......................................................................................................... 50
3.2.1 Navigation Tools of the Screen..................................................................................... 50
3.2.2 Display Elements in the Diagram Area......................................................................... 55
3.2.3 Dialogs.......................................................................................................................... 63
3.2.4 Display Formats and Diagram Types............................................................................67
3.3 Measured Quantities...................................................................................................75
3.3.1 S-Parameters................................................................................................................ 76
3.3.2 Impedance Parameters.................................................................................................77
3.4 Calibration................................................................................................................... 87
3.4.1 Calibration Standards and Calibration Kits................................................................... 88
3.4.2 Calibration Types.......................................................................................................... 89
3.4.3 Automatic Calibration.................................................................................................... 90
3.4.4 Power Calibration..........................................................................................................93
3.4.5 Offset Parameters......................................................................................................... 93
3.5 Optional R&S ZVA Extensions...................................................................................94
3.5.1 Time Domain (R&S ZVAB-K2)...................................................................................... 95
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R&S® ZVA
3.5.10 Internal Pulse Generators (R&S ZVA-K27)...................................................................98
3.5.11 Noise Figure Measurement (R&S ZVAB-K30).............................................................. 98
3.5.12 Frequency Converting Noise Figure Measurement (R&S ZVA-K31)............................ 98
Contents
3.5.2 Arbitrary Generator and Receiver Frequencies (R&S ZVA-K4).................................... 95
3.5.3 Arbitrary Gen. and Rec. Frequencies (R&S ZVA-K4)................................................... 95
3.5.4 Mixer Phase Measurement (R&S ZVA-K5)...................................................................96
3.5.5 True Differential Mode (R&S ZVA-K6).......................................................................... 96
3.5.6 Measurements on Pulsed Signals (R&S ZVA-K7)........................................................ 97
3.5.7 Converter Control (R&S ZVA-K8)................................................................................. 97
3.5.8 Mixer Delay w/o LO Access (R&S ZVA-K9)..................................................................97
3.5.9 Long Distance Mixer Delay (R&S ZVA-K10).................................................................98
Glossary: Frequently Used Terms......................................................99
Index....................................................................................................105
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R&S® ZVA
Contents
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R&S® ZVA
Preparing the Analyzer for Use
Front Panel Tour
1 Preparing the Analyzer for Use
This chapter gives an overview of the front panel controls and connectors of the network analyzer and gives all information that is necessary to put the instrument into
operation and connect external devices. Notes on reinstallation of the analyzer software appear at the end of the chapter.
Risk of injury and instrument damage
The instrument must be used in an appropriate manner to prevent electric shock, fire,
personal injury, or damage.
●
Do not open the instrument casing.
●
Read and observe the "Basic Safety Instructions" at the beginning of this manual or
on the documentation CD-ROM, in addition to the safety instructions in the following sections. Notice that the data sheet may specify additional operating conditions.
Chapter 2 of this manual provides an introduction to the operation of the analyzer by
means of typical configuration and measurement examples; for a description of the
operating concept and an overview of the instrument’s capabilities refer to chapter 3,
"System Overview", on page 45. For all reference information concerning manual
and remote control of the instrument refer to your analyzer's help system or its printed/
printable version. A more detailed description of the hardware connectors and interfaces is also part of the help system.
1.1 Front Panel Tour
The front panel of the network analyzer consists of the VGA display with the softkey
area (left side), the hardkey area (right side) and the test port area below. Brief explanations on the controls and connectors, the hardkey area and the rear panel can be
found on the next pages.
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Preparing the Analyzer for Use
Front Panel Tour
Fig. 1-1: R&S ZVA front view
1.1.1 Display
The analyzer is equipped with a color display providing all control elements for the
measurements and the diagram areas for the results.
●
Refer to chapter 3.2.1, "Navigation Tools of the Screen", on page 50 to learn how
to use menus, keys and softkeys.
●
Refer to chapter 3.2.2, "Display Elements in the Diagram Area", on page 55 to
obtain information about the results in the diagram area.
●
Refer to section "Display Menu" in the help system and learn how to customize the
screen.
●
Refer to the data sheet for the technical specifications of the display.
Screen saver
The screen saver function of the operating system switches off the display if the analyzer receives no command for a certain time. It is switched on again if any front panel
key is pressed. Use the Windows control panel to change the screen saver properties
(press the Windows key in the SUPPORT keypad to access the Start menu).
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Front Panel Tour
Short screen flicker
On instruments equipped with an FMR7 front module controller, you may observe a
short screen flicker when accessing the Windows desktop. The flicker does not occur
while the network analyzer is running; it does not impair the functionality of the instrument.
1.1.2 Setup Keys
The keys in the TRACE, CHANNEL, DISPLAY, SYSTEM and SUPPORT keypads call
up groups of related measurement settings. Each key corresponds to a drop-down
menu or menu command of the graphical user interface.
The TRACE keys give access to all trace settings and the functions to select, modify
and store different traces. In addition the menu provides the marker, search and limit
check functions.
●
MEAS selects the quantity to be measured and displayed.
●
FORMAT defines how the measured data is presented in the graphical display.
●
SCALE defines how the current trace is presented in the diagram selected in the
Format submenu.
●
TRACE SELECT provides functions to handle traces and diagram areas, and
assign traces to channels.
●
LINES defines limits for measured values and activates the limit check.
●
TRACE FUNCT(ions) store traces to the memory and perform mathematical operations on traces.
●
MARKER positions markers on a trace, configures their properties and selects the
format of the numerical readout.
●
SEARCH uses markers to locate specific points on the trace.
●
MARKER FUNCT(ions) define the sweep range, scale the diagram and introduce
an electrical length offset using the active marker.
The CHANNEL keys give access to all channel settings and the functions to activate,
modify and store different channels.
●
START CENTER or STOP SPAN define the sweep range, depending on the
sweep type.
●
POWER BW AVG defines the power of the internal signal source, sets the step
attenuators and the IF bandwidths, and configures the sweep average.
●
SWEEP defines the scope of measurement, including the sweep type, the trigger
conditions and the periodicity of the measurement.
●
MODE opens the Port Configuration dialog to define the properties of the physical
and logical (balanced) test ports.
●
CHAN SELECT provides functions to handle and activate channels.
●
CAL provides all functions that are necessary to perform a system error correction
(calibration).
●
OFFSET provides a selection of length offset parameters to shift the measurement
plane.
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Front Panel Tour
The DISPLAY keys give access to all display settings and to the functions to activate,
modify and arrange different diagram areas.
●
AREA SELECT provides functions to create and delete diagram areas and select
an area as the active area.
●
DISPLAY CONFIG provides functions to arrange traces to diagram areas, arrange
the diagram areas in the active window and configure the screen and the diagram
areas.
The SYSTEM keys give access to the functions to return to a defined instrument state
and select general system settings.
●
PRESET performs a general factory preset or user preset.
●
SYSTEM CONFIG selects general system settings which do not only apply to a
particular setup.
A second group of keys (uncolored) provides standard Windows™ functions to save,
recall or print setups and call up the measurement wizard.
●
SAVE saves an opened setup to a specific file.
●
RECALL recalls an existing setup from a file.
●
PRINT prints a setup.
The SUPPORT keys give access to the functions to reverse operations, retrieve information on the instrument and obtain assistance.
●
UNDO reverses the previous operation.
●
INFO calls up a table providing information about the current setup.
●
HELP calls up the on-line help system.
A second group of keys (uncolored) is used to navigate within the graphical user interface:
●
MENU sets the cursor to the first item (File) in the menu bar of the active application (network analyzer or help system) if no dialog is open. In the network analyzer
(NWA) application, menus are equivalent to softkeys and provide fast access to all
instrument functions. The menus in the help system are required for accessing all
help functions by means of the front panel keys. In NWA dialogs, the MENU key
opens the control menu to move or close the dialog.
●
The Windows key opens the Windows Startup menu from where it is possible to
perform system configurations and call up additional software utilities.
1.1.3 Navigation Keys
The keys in the NAVIGATION keypad are used to navigate within the NWA screen and
the help system, to access and control active elements.
The ⇤ FIELD (= Tab) and ⇥ FIELD (= Shift Tab) keys switch between several active
elements in dialogs and panes, e.g. in order to access:
●
All control elements (e.g. buttons, numerical or text input fields, radio buttons,
checkmarks, combo boxes etc.) in a dialog
●
All links in a Help topic
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Preparing the Analyzer for Use
Front Panel Tour
The ↑ (cursor up) and ↓ (cursor down) keys are used to:
●
Scroll up and down in lists, e.g. among menu items, in a list of keywords, in the
Help table of contents, or in the Help topic text
●
Increase and decrease numeric input values
↑ (↓) become inactive as soon as the beginning (end) of the list is reached. ↑ (↓) is
equivalent to a rotation of the rotary knob to the right (left).
The ← (cursor left) and → (cursor right) keys are used to:
●
Move the cursor to the left or right within input fields
●
Compress or expand menus or the Help table of contents
●
Move the highlighted item in the menu bar of the active application
OK ENTER is used to:
●
Activate the selected active control element, e.g. a button in a dialog or a link in the
Help
●
Confirm selections and entries made and close dialogs
OK ENTER is equivalent to pressing the rotary knob or the OK ENTER key in the
DATA ENTRY keypad.
The ☑ (= Space) key switches a checkmark control in a dialog on or off.
The CANCEL ESC key is used to:
●
Close dialogs without activating the entries made (equivalent to the "Close" button)
●
Close the Help
CANCEL ESC is equivalent to the CANCEL ESC key in the DATA ENTRY keypad.
1.1.4 Data Entry Keys
The keys in the DATA ENTRY keypad are used to enter numbers, units, and characters.
The data entry keys are only enabled while the cursor is placed on a data input field in
a dialog or in the Help navigation pane.
The keys 0 to 9 enter the corresponding numbers.
The function of the "." and "–" keys depends on the data type of the active input field:
●
In numeric input fields, the keys enter the decimal point and change the sign of the
entered numeric value. Multiple decimal points are not allowed; pressing "–" for a
second time cancels the effect of the first entry.
●
In character input fields, the keys enter a dot and a hyphen, respectively. Both
entries can be repeated as often as desired.
The function of the four unit keys depends on the data type of the active input field; see
chapter 2.3.2, "Data Entry", on page 39.
●
In numeric input fields (e.g. in the numeric entry bar), the G/n, M/μ, k/m or x1 keys
(-)9
(-)6
multiply the entered value with factors of 10
, 10
(-)3
, 10
or 1 and add the appro-
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Preparing the Analyzer for Use
Front Panel Tour
priate physical unit. x1 is equivalent to OK ENTER. It confirms the previous entry
and deactivates the input field (closes the numeric entry bar).
●
In character input fields, the G/n, M/μ, k/m keys enter the letters G, M, K, respectively. x1 is equivalent to OK ENTER. It confirms the previous entry and deactivates the input field.
The ESC CANCEL and OK ENTER keys are equivalent to the corresponding keys in
the NAVIGATION keypad.
BACK deletes the last character before the cursor position or the selected character
sequence. If an entire numeric value is selected, BACK moves the cursor in front of the
first digit.
1.1.5 Rotary Knob
The rotary knob increases and decreases numerical values, scrolls within lists, activates controls and confirms entries. Turning or pressing the rotary knob is equivalent to
the action of the ↑ and ↓ keys or the OK ENTER key in the NAVIGATION keypad.
STEP SIZE opens an input box to select the steps (in units of the current physical
parameter) between two consecutive values if the rotary knob is turned to increase or
decrease numeric values. See chapter 3.2.3.3, "Step Size", on page 65.
1.1.6 Standby Key
The standby toggle switch is located in the bottom left corner of the front panel.
The key serves two main purposes:
●
Toggle between standby and ready state.
●
Shut down the instrument.
1.1.7 Front Panel Connectors
The test ports and various additional connectors are located on the front panel of the
analyzer.
1.1.7.1 Test Ports
N-connectors (or smaller ruggedized connectors for microwave analyzer types), numbered 1, 2 ... The test ports serve as outputs for the RF stimulus signal and as inputs
for the measured RF signals from the DUT (response signals).
●
With a single test port, it is possible to generate a stimulus signal and measure the
response signal in reflection.
●
With 2, 3 or 4 test ports, it is possible to perform full two-port, 3-port or 4-port measurements; see chapter 3.3.1, "S-Parameters", on page 76. Note that for most
R&S ZVA models, ports 2k-1 and 2k share a common generator; only for
R&S ZVA24 with 4 ports and 4 generators (order no. 1145.1110.28), R&S ZVA40
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Front Panel Tour
with 4 ports and 4 generators (order no. 1145.1110.48) and R&S ZVA67 all test
ports are equipped with independent sources.
●
Each test port may be complemented by three pairs of additional connectors used
to test high power devices and extend the dynamic range, see chapter 1.1.7.4,
"Direct Generator and Receiver Access", on page 14.
Maximum input levels
The maximum input levels at all test ports according to the front panel labeling or the
data sheet must not be exceeded.
In addition, the maximum input voltages of the other input connectors at the front and
rear panel must not be exceeded.
The three LEDs above each test port indicate the connector state:
●
The amber LED is on while the connector is used as a source port.
●
The green LED is on while the connector is used as a bidirectional (source and
receive) port.
●
The blue LED is on while the connector is used as a receive port.
It is recommended to use a torque wrench when screwing RF cables on the test port
connectors. Standard IEEE 287 specifies a torque of (1.5 ± 0.2) Nm for N connectors,
(0.9 ± 0.1) Nm for the microwave connector types.
1.1.7.2 USB Connectors
Double Universal Serial Bus connector of type A (master USB), used to connect e.g a
keyboard, mouse or other pointing devices, the Calibration Unit (accessory R&S ZVZ5x), a printer or an external storage device (USB stick, CD-ROM drive etc.).
To control external devices (e.g. power meters, generators) via USB connector, a VISA
installation on the network analyzer is required. Use the USB-to-IEC/IEEE Adapter
(option R&S ZVAB-B44) to control devices equipped with a GPIB interface.
The length of passive connecting USB cables should not exceed 1 m. The maximum
current per USB port is 500 mA. See also chapter 1.3.5, "EMI Suppression",
on page 20.
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Preparing the Analyzer for Use
Front Panel Tour
R&S ZVAB-B44 on network analyzers with FMR7/6 and FMR9
The driver software of the USB-to-IEC/IEEE Adapter (option R&S ZVAB-B44) must be
installed on the network analyzer. On analyzers equipped with an FMR7/6 or FMR9
front module controller, this installation disables GPIB control from an external PC. A
reinstallation of the NWA firmware (e.g. in repair mode) will resolve the problem; see
chapter 1.9, "Firmware Update", on page 29.
1.1.7.3 Ground Connector
Connector providing the ground of the analyzer's supply voltage.
Electrostatic discharge
Electrostatic discharge (ESD) may cause damage to the electronic components of the
DUT and the analyzer. Use the wrist strap and cord supplied with the instrument to
connect yourself to the GND connector.
1.1.7.4 Direct Generator and Receiver Access
Option R&S ZVA<n>-B16, Direct Generator/Receiver Access, provides 3 pairs of SMA
connectors (or smaller connectors, for microwave analyzers) for each test port. <n>
corresponds to the network analyzer type. For detailed ordering information refer to the
product brochure. See also section "Converter Control" in the help system of your network analyzer.
The connectors give direct access to various RF input and output signals. They can be
used to insert external components (e.g. external signal separating devices, power
amplifiers, a ZVAX extension unit etc.) into the signal path in order to develop custom
measurements, e.g. to test high power devices and extend the dynamic range. If no
external components are connected, each OUT/IN loop should be closed using a
jumper.
●
The SOURCE OUT signal comes from the internal RF signal source. The
SOURCE IN signal goes to the test port. A power amplifier can be inserted
between SOURCE OUT and SOURCE IN in order to boost the test port power.
●
The REF OUT signal comes from the coupler and provides the reference signal.
The REF IN signal goes to the receiver input for the reference signal.
●
The MEAS OUT signal comes from the coupler and provides the received (measured) signal. The MEAS IN signal goes to the receiver input for the measured signal.
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R&S® ZVA
Preparing the Analyzer for Use
Rear Panel Tour
Input signals
The maximum RF input levels at all SMA inputs according to the front panel labeling or
the data sheet must not be exceeded.
In addition, it is important that the signal fed in at the SMA inputs contains no DC offset, as this may impair the measurements and even cause damage to the instrument.
1.1.8 Additional Hardware Options
The following hardware options can be mounted on the right of the NAVIGATION and
SUPPORT keypads:
●
Option R&S ZVA-B18, Removable Hard Disk, replaces the internal hard disk by a
removable compact flash card. The compact flash card can be inserted at the front
panel of the instrument. To ensure failure-free operation, avoid placing external
cables close to the compact flash card.
●
Option R&S ZVA-B8, Converter Control, provides output connectors to control the
output power of a frequency converter with external attenuators, R&S ZVA-ZxxxE.
This option is available for R&S ZVA network analyzers with an upper frequency
limit of 20 GHz or higher (R&S ZVA 24, R&S ZVA40 ...). For information on measurements with external attenuators, refer to the network analyzer's help system
and to the Getting Started guide R&S ZVA-ZxxxE, stock no. 1307.7197.62.
Contact your R&S service representative, if you wish to obtain and install one of the
additional hardware options.
1.2 Rear Panel Tour
This section gives an overview of the rear panel controls and connectors of the network analyzer.
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R&S® ZVA
Preparing the Analyzer for Use
Rear Panel Tour
Fig. 1-2: R&S ZVA rear view
The rear connectors are described in detail in the annex "Hardware Interfaces" in the
help system.
●
The PORT BIAS panel contains inputs for an external DC voltage (bias) to be
applied to the test ports. A separate input is provided for each test port. Each
PORT BIAS input is protected by an exchangeable fuse.
●
IEC Bus is the GPIB bus connector (according to standard IEEE 488 / IEC 625).
●
AUX is an auxiliary connector, to be wired as needed. AUX is not fitted on standard
instruments.
●
LAN 1 and LAN 2 are two equivalent connectors to connect the analyzer to a Local
Area Network.
●
USB is a double Universal Serial Bus connector of type A (master USB), used to
connect a keyboard, mouse or other pointing device.
●
DC MEAS comprises two inputs for DC measurements, specified for different voltage ranges.
●
10 MHz REF serves as an input or output for the 10 MHz reference clock signal.
●
MONITOR is a sub-Min-D connector used to connect an external VGA monitor.
●
CASCADE is a 8-pin RJ-45 connector used as output and input connectors for
pulse generator signals. The CASCADE connector is located between the MONITOR and the USER CONTROL connectors.
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R&S® ZVA
Preparing the Analyzer for Use
Putting the Analyzer into Operation
●
USER CONTROL is a D-sub connector used as an input and output for low-voltage
(3.3 V) TTL control signals.
●
EXT. TRIGGER is an input for a low-voltage (3.3 V) TTL external trigger signal.
Input levels, EMC
The maximum input levels and voltages of the input connectors at the front and rear
panel must not be exceeded.
The EXT TRIGGER input connector and pin 2 of the USER CONTROL connector must
never be used simultaneously as inputs for external trigger signals.
Use double shielded cables at the BNC rear panel connectors (10 MHz REF, PORT
BIAS, EXT. TRIGGER) and match signals with 50 Ω in order to comply with EMC
directives!
1.3 Putting the Analyzer into Operation
This section describes the basic steps to be taken when setting up the analyzer for the
first time.
Risk of injury and instrument damage
The instrument must be used in an appropriate manner to prevent electric shock, fire,
personal injury, or damage.
●
Do not open the instrument casing.
●
Read and observe the "Basic Safety Instructions" at the beginning of this manual or
on the documentation CD-ROM, in addition to the safety instructions in the following sections. Notice that the data sheet may specify additional operating conditions.
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R&S® ZVA
Preparing the Analyzer for Use
Putting the Analyzer into Operation
Risk of instrument damage during operation
An unsuitable operating site or test setup can cause damage to the instrument and to
connected devices. Ensure the following operating conditions before you switch on the
instrument:
●
All fan openings are unobstructed and the airflow perforations are unimpeded. The
minimum distance from the wall is 10 cm.
●
The instrument is dry and shows no sign of condensation.
●
The instrument is positioned as described in the following sections.
●
The ambient temperature does not exceed the range specified in the data sheet.
●
Signal levels at the input connectors are all within the specified ranges.
●
Signal outputs are correctly connected and are not overloaded.
1.3.1 Unpacking and Checking the Analyzer
To remove the instrument from its packaging and check the equipment for completeness proceed as follows:
1. Pull off the polyethylene protection pads from the instrument's rear feet and then
carefully remove the pads from the instrument handles at the front.
2. Pull off the corrugated cardboard cover that protects the rear of the instrument.
3. Carefully unthread the corrugated cardboard cover at the front that protects the
instrument handles and remove it.
4. Check the equipment for completeness using the delivery note and the accessory
lists for the various items.
5. Check the instrument for any damage. If there is damage, immediately contact the
carrier who delivered the instrument.
Retain the original packing material. If the instrument needs to be transported or shipped at a later date, you can use the material to prevent control elements and connectors from being damaged.
1.3.2 Setting up the Analyzer
The network analyzer is designed for use under laboratory conditions, either on a
bench top or in a rack. The general ambient conditions required at the operating site
are as follows:
●
The ambient temperature must be in the ranges specified for operation and for
compliance with specifications (see data sheet).
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Putting the Analyzer into Operation
●
All fan openings including the rear panel perforations must be unobstructed. The
distance to the wall should be at least 10 cm.
Electrostatic discharge
To avoid damage of electronic components of the DUT and the analyzer, the operating
site must be protected against electrostatic discharge (ESD). ESD is most likely to
occur when you connect or disconnect a DUT or test fixture to the analyzer's test ports.
To prevent ESD damage use the wrist strap and grounding cord supplied with the
instrument and connect yourself to the GND connector at the front panel.
1.3.3 Bench Top Operation
If the analyzer is operated on a bench top, the surface should be flat. The instrument
can be used in horizontal position, standing on its feet, or with the support feet on the
bottom extended.
Danger of injury
The feet may fold in if they are not folded out completely or if the instrument is shifted.
The feet may break if they are overloaded. Fold the feet completely in or completely
out to ensure stability of the instrument and personal safety. To avoid injuries, never
shift the instrument when its feet are folded out.
The overall load (the instrument's own weight plus that of the instruments stacked on
top of it) on the folded-out feet must not exceed 500 N.
Place the instrument on a stable surface. Secure the instruments stacked on top of it
against slipping (e.g. by locking their feet on the top front frame). When the instrument
is standing on its folded-out feet, do not work under the instrument and do not put anything under it, otherwise injuries or material damage could occur.
The instrument can be used in each of the positions shown here.
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Putting the Analyzer into Operation
1.3.4 Operation in a 19" Rack
Using the adapter R&S ZZA-611 (order number 1096.3302.00) the instrument can be
mounted in 19" racks according to the mounting instructions supplied with the rack
adapter.
Avoid overheating
●
Allow for sufficient air supply in the rack.
●
Make sure that there is sufficient space between the ventilation holes and the rack
casing.
1.3.5 EMI Suppression
To suppress generated Electromagnetic Interference (EMI), operate the instrument
only while it is closed, with all shielding covers fitted. Note the EMC classification in the
data sheet.
Use appropriate shielded cables to ensure successful control of electromagnetic radiation during operation, especially for the following connector types:
●
BNC rear panel connectors (10 MHz REF, EXT. TRIGGER): Use double shielded
cables and terminate open cable ends with 50 Ω.
●
USER CONTROL: Use only well shielded cables or disconnect the input pins of the
USER CONTROL connector in order to avoid spurious input signals which may
cause undesirable events. This is of particular importance for the external trigger
input (pin no. 2) if the EXT TRIGGER input is used.
●
USB: Use double-shielded USB cables and ensure that external USB devices comply with EMC regulations.
●
GPIB (IEEE/IEC 625): Use a shielded GPIB cable.
●
LAN: Use CAT6 or CAT7 cables.
●
Test ports: For instruments with 3.5 mm and smaller connector types (2.92 mm, 2.4
mm ...), use double-shielded measurement cables.
The use of external accessories for the network analyzers may introduce additional
connector, cable, and cable length requirements. Refer to the relevant documentation.
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Preparing the Analyzer for Use
Putting the Analyzer into Operation
1.3.6 Connecting the Analyzer to the AC Supply
The network analyzer is automatically adapted to the AC supply voltage supplied. The
supply voltage must be in the range 100 V to 240 V; 50 Hz to 60 Hz. The mains connector is located at the bottom left corner of the rear panel.
► Connect the network analyzer to the AC power source using the AC power cable
delivered with the instrument.
The maximum power consumption of the analyzer is 450 W. The typical power consumption is listed in the "Specifications".
The network analyzer is protected by two fuses as specified on the label on the power
supply. The fuses are located on an AC Fuse Board (order no. 1145.3906.02) which
must be replaced to change the fuses. Replacing the AC Fuse Board requires opening
the instrument and is described in the service manual.
1.3.7 Power on and off
The mains connector is located at the bottom left corner of the rear panel.
► To turn the power on or off, press the AC power switch to position I (On) or 0 (Off).
After power-on, the analyzer is in standby or ready state, (see chapter 1.3.8, "Standby
and Ready State", on page 21) depending on the state of the STANDBY toggle
switch at the front panel when the instrument was switched off for the last time.
The AC power switch can be permanently on. Switching off is required only if the
instrument must be completely removed from the AC power supply.
1.3.8 Standby and Ready State
The STANDBY toggle switch is located in the bottom left corner of the front panel.
► After switching on the AC power (see chapter 1.3.7, "Power on and off",
on page 21) press the STANDBY key briefly to switch the analyzer from the
standby to ready state or vice versa.
●
In standby state, the right, amber LED is on. The standby power only supplies the
power switch circuits and the optional oven quartz (OCXO, 10 MHz reference oscillator, option R&S ZVAB-B4, order no. 1164.1757.02). In this state it is safe to
switch off the AC power and disconnect the instrument from the power supply.
●
In ready state, the left, green LED is on. The analyzer is ready for operation. All
modules are power-supplied and the analyzer initiates its startup procedure.
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Starting the Analyzer and Shutting Down
Shock hazard
The instrument is still power-supplied while it is in standby mode.
1.3.9 Replacing Fuses
The DC inputs PORT BIAS at the rear panel are each protected by a fuse IEC 127 - F
250 L (250 mA quick acting).
► To replace the fuses open the fuse holder by slightly turning the lid counterclock-
wise.
Replacement fuses are provided with the instrument.
1.4 Starting the Analyzer and Shutting Down
To start the analyzer, proceed as follows:
1. Make sure that the instrument is connected to the AC power supply and the power
switch on the rear panel is in position I (On).
2. If necessary, press the STANDBY toggle switch on the front panel to switch the
instrument to ready state (the green LED is on).
In ready state, the analyzer automatically performs a system check, boots the Windows® operating system and then starts the network analyzer (NWA) application. If the
last analyzer session was terminated regularly, the NWA application uses the last
setup with all instrument settings.
To shut down the analyzer, proceed as follows:
1. Press the STANDBY key to save the current setup, close the NWA application,
shut down Windows® and set the instrument to standby state. Of course you can
also perform this procedure step by step like in any Windows session.
2. If desired, set the AC power switch to position 0 (Off).
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Windows Operating System
Risk of data loss
It is strongly recommended to switch the analyzer to standby state before disconnecting it from the AC supply. If you set the power switch to 0 while the NWA application is
still running, you will lose the current settings. Moreover, loss of program data can not
be excluded if the application is terminated improperly.
Minimizing the NWA application
With a minimized NWA application, you can access your analyzer's Windows® desktop
or run other applications. To start the NWA application with a minimized window on a
continuing basis, right-click the NWA shortcut icon on the desktop and open the "Properties" dialog. In the "Shortcut" tab, select "Run: Minimized".
After a software update the NWA application is started with a maximized window
again. Moreover, if a second NWA application is started after a first, minimized application, this will cause the first application to come to the foreground.
1.5 Windows Operating System
The analyzer is equipped with a Windows XP or Windows 7 operating system that has
been configured according to the instrument's features and needs.
Support for Windows 7 was added with FW version 3.50 and requires the analyzer to
be equipped with the new CPU board FMR11.
Upgrade kits from FMR6/7/9 to FMR11 with Windows 7 are available as option
R&S ZVA-U116. Note however that FMR11 is not supported with Windows XP.
Changes in the system configuration can be necessary in order to:
●
Customize the properties of the external accessories connected to the analyzer,
e.g. the screen resolution of a connected monitor
●
Establish a LAN connection
●
Call up additional software tools
Modifications of the operating system
The operating system is adapted to the network analyzer. To avoid impairment of
instrument functions, only change the settings described in this manual. Existing software must be modified only with update software released by Rohde & Schwarz. Likewise, only programs authorized by Rohde & Schwarz for use on the instrument must
be executed.
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Connecting External Accessories
The "Start" menu of the operating system is accessed by pressing the Windows key in
the SUPPORT keypad. All necessary settings can be accessed from the "Start" menu,
in particular from the Control Panel.
1.6 Connecting External Accessories
The equivalent USB ports on the front and rear panel of the analyzer can be used to
connect a variety of accessories:
●
A mouse simplifies operation of the instrument using the controls and dialogs of
the Graphical User Interface (GUI).
●
A keyboard simplifies the entry of data; the default input language is English – US.
●
A printer generates hard copies of the screen contents. When printing a copy
("File – Print"), the analyzer checks whether a printer is connected and turned on
and whether the appropriate printer driver is installed.
If required, printer driver installation is initiated using the Windows "Add Printer"
wizard. The wizard is self-explanatory. A printer driver needs to be installed only
once, even though the printer may be temporarily removed from the analyzer.
It is safe to connect or disconnect mouse, keyboard or printer during the measurement.
A standard VGA monitor or LCD display can be connected to the 15-pole Sub-Min-D
MONITOR connector on the rear panel of the analyzer.
It displays the magnified Graphical User Interface (GUI) with all diagram areas. If
desired, click "Display – Config/View – Hardkey Bar" to add the "Hardkey Bar" (front
panel key bar) to the analyzer screen.
Safety aspects
The monitor must be connected while the instrument is switched off (or in standby
mode). Otherwise correct operation can not be guaranteed.
Typically mouse, keyboard and monitor are plug & play devices, i.e. they are automatically detected by the operating system. If necessary, use standard Windows techniques (such as the "Add Printer " wizard or the device properties pages accessible via
Windows Control Panel) to install missing or enhanced device drivers and to configure
connected devices.
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Connecting to a LAN
1.7 Connecting to a LAN
A LAN connection is used to integrate the analyzer into a home/company network. This
offers several applications, e.g.:
●
Transfer data between a controller and the analyzer, e.g. in order run a remote
control program.
●
Control the measurement from a remote computer using the Remote Desktop
application.
●
Use external network devices (e.g. printers).
Virus protection
An efficient virus protection is a prerequisite for secure operation in the network. Never
connect your analyzer to an unprotected network because this may cause damage to
the instrument software.
1.7.1 Physical LAN Connection
A LAN cable can be connected to one of the LAN connectors on the rear panel of the
analyzer. To establish a LAN connection proceed as follows:
1. Refer to section TCP/IP Configutation and learn how to avoid connection errors.
2. Connect a CAT6 or CAT7 RJ-45 (LAN, Ethernet) cable to one of the LAN ports.
The LAN ports of the analyzer are auto-crossover Ethernet ports. You can connect
them to a network that is equipped with Ethernet hardware (hub, switch, router), but
you can also set up a direct connection to a computer or another test instrument. For
both connection types, you can use either crossover or standard straight-through
Ethernet cables.
1.7.2 TCP/IP Configutation
Depending on the network capacities, the TCP/IP configuration for the analyzer can be
obtained in different ways.
●
If the network supports dynamic TCP/IP configuration using the Dynamic Host
Configuration Protocol (DHCP), the configuration can be assigned automatically.
●
If the network does not support DHCP, or if the analyzer is set to use manual
TCP/IP configuration, the configuration must be entered manually.
The active TCP/IP configuration is displayed in the "Instrument Information" section of
the"Info > Setup Info" dialog.
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Connecting to a LAN
By default, the analyzer is configured to use dynamic TCP/IP configuration. This
means that it is safe to establish a physical connection to the LAN without any previous
analyzer configuration.
Manual TCP/IP configuration
If your network does not support DHCP, or if you choose to disable dynamic TCP/IP
configuration, you must enter a valid TCP/IP configuration before connecting the analyzer to the LAN. Contact your network administrator, because connection errors can
affect the entire network.
For more information refer to the Windows "Help and Support Center".
To disable dynamic TCP/IP configuration and enter the TCP/IP address information
manually proceed as follows:
1. Obtain the IP address and subnet mask for the analyzer and the IP address for the
local default gateway from your network administrator. If needed, also obtain the
name of your DNS domain and the IP addresses of the DNS and WINS servers on
your network. If you use both LAN connectors, you need two different sets of
address information.
2. Press the Windows key to access the Start Menu and from there open the Control
Panel.
3. For each LAN interface to be configured, enter the IPv4 protocol stack configuration provided by your network administrator, e.g.
Windows XP: "Control Panel – Network Connections – Local Area Connection Status – Local Area Connection Properties – Internet Protocol (TCP/IP) Properties"
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Connecting to a LAN
Windows 7: "Control Panel – Network and Internet – Network and Sharing Center –
Change adapter settings – Change Settings of this conection – Internet Protocol
version 4 (TCP/IPv4) Properties"
LXI compliance
Analyzers running under Windows XP (SP 2 or higher) comply with LXI class C, which
enables remote access to an instrument's LAN settings; see "LXI Configuration" in your
analyzer's help system.
1.7.3 Test Setups with two LAN Connections
The two LAN connectors on the rear panel of the analyzer are equivalent. With one
LAN connector used to establish a connection to a home/company network, the other
one can be used to connect an additional instrument, e.g. an additional analyzer or signal generator.
Defining the network topology: Router vs. network client
With two LAN connections, it is possible to use the analyzer in two alternative ways:
●
As a client participating in two independent networks, one comprising the home
network including the analyzer, the second consisting of the additional test instrument plus the analyzer.
●
As a data router between the additional test instrument and the home network.
This configuration means that the analyzer and the additional test instrument are
integrated into a single network.
The network topology is defined in Windows' "Advanced TCP/IP Settings" dialog:
"Windows XP Control Panel – Network Connections – Local Area Connection Status –
Local Area Connection Properties – Internet Protocol (TCP/IP) Properties – Advanced"
"Windows 7 Control Panel – Network and Internet – Network and Sharing Center –
Change adapter settings – Change Settings of this conection – Internet Protocol version 4 (TCP/IPv4) Properties – Advanced"
Both instruments must have independent IP addresses; see chapter 1.7.2, "TCP/IP
Configutation", on page 25. Contact your LAN administrator for details.
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Remote Desktop Connection
Avoid parallel connections
Never use both LAN connectors to connect the analyzer in parallel to the same network as this will result in connection errors.
1.8 Remote Desktop Connection
Remote Desktop is a Windows® application which can be used to access and control
the analyzer from a remote computer through a LAN connection. While the measurement is running, the analyzer screen contents are displayed on the remote computer,
and Remote Desktop provides access to all of the applications, files, and network
resources of the analyzer.
On analyzers running Windows 7, by default remote connections are enabled using a
local group policy and remote access is granted to users instrument and administrator.
To enable remote connections to an instrument running Windows XP, proceed as follows:
1. As described above, connect the analyzer to the LAN and configure the LAN
TCP/IP interface (see chapter 1.7, "Connecting to a LAN", on page 25).
Memorize the analyzer's IP address ("Info – Setup Info – Instrument Information" at
the NWA GUI).
2. At the analyzer, press the Windows button to access the start menu and open the
Control Panel.
3. Allow remote desktop connections ("Control Panel – System – Properties –
Remote tab – Allow users to connect remotely to this computer")
To set up the connection, run the Remote Desktop Connection application at the
remote Windows PC and connect to the analyzer's IP address.
Password protection
The analyzer uses a user name and password as credentials for remote access. In the
factory configuration, the user name is "instrument"; the password is "894129". To protect the analyzer from unauthorized access, it is recommended to change the factory
setting.
On network analyzers equipped with a Windows XP version earlier than 5.1 Service
Pack 3, "instrument" is preset for both the user name and the password. The Windows
XP version appears in the "Info" dialog ("Info > Setup Info > Instrument Information") or
in the "System Properties" dialog of Windows XP's control panel ("Start Settings >
Control Panel > System > General").
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Firmware Update
For detailed information about Remote Desktop refer to the Windows® Help.
1.9 Firmware Update
Upgrade versions of the analyzer firmware are supplied as single setup files *.msi. To
perform a firmware update,
1. Copy the setup file to any storage medium accessible from the analyzer. This may
be the internal hard disk, an external storage medium (USB memory stick, CDROM with external drive) or a network connection (LAN, GPIB bus).
2. Double-click the setup file (or use the front panel keys to select and start the setup
file; see chapter 2.3.2.1, "Using Front Panel Keys", on page 39) and follow the
instructions of the setup wizard.
Setup files can be stored and installed again. The default drive letter of the internal
hard disk is "C". External storage devices are automatically mapped to the next free
drive letters "D", "E" etc.
Factory calibration
A firmware update does not affect the factory calibration.
External accessories
Calibration units and extension Units must be disconnected during a firmware update.
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Performing a Reflection Measurement
2 Getting Started
The following chapter presents a sample session with a R&S ZVA network analyzer
using an external monitor and the Graphical User Interface and explains how to solve
basic tasks that you will frequently encounter when working with the instrument.
Safety considerations
Before starting any measurement on your network analyzer, please note the instructions given in Preparing the Analyzer for Use.
In the System Overview chapter below you will find detailed information on customizing
the instrument and the display according to your personal preferences. For a systematic explanation of all menus, functions and parameters and background information
refer to the "GUI Reference" chapter in the help system.
Use the "S-Parameter Wizard" in the "System" menu to perform a standard S-parameter measurement in a straightforward way. The wizard provides a series of dialogs
where you can select the test setup, screen configuration and measurement parameters, configure the essential channel settings and perform a guided calibration.
Measurement stages in the wizard
The different dialogs of the S-parameter wizard correspond to the typical stages of any
measurement:
1. Select the test setup
2. Select the measurement parameters and the diagram areas
3. Define the sweep range
4. Adjust the receiver and source settings (measurement bandwidth, source power)
5. Perform a calibration
In the following we assume that you are familiar with standard Windows dialogs and
mouse operation. Refer to chapter 2.3.1, "Control via Front Panel Keys", on page 37
and chapter 2.3.2, "Data Entry", on page 39 to learn how to access instrument functions and control dialogs without a mouse and keyboard.
2.1 Performing a Reflection Measurement
In a reflection measurement, the analyzer transmits a stimulus signal to the input port
of the device under test (DUT) and measures the reflected wave. A number of trace
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Getting Started
Performing a Reflection Measurement
formats allow you to express and display the results. depending on what you want to
learn from the data. Only one analyzer test port is required for reflection measurements.
In the following example, the analyzer is set up for a reflection measurement, a frequency sweep range and measurement parameter is selected, the instrument is calibrated and the result is evaluated using various formats.
2.1.1 Instrument Setup for Reflection Measurements
In order to prepare a reflection measurement, you have to connect your DUT (which for
simplicity we assume to have an appropriate connector, e.g. a male N 50 Ω connector)
to one of the (equivalent) analyzer test ports. Besides, it is recommended to preset the
instrument in order to set it to a definite, known state.
1. Proceed as described in chapter 1.4, "Starting the Analyzer and Shutting Down",
on page 22 to switch on the instrument and start the NWA application.
2. Connect the input port of your DUT to test port 1 of the network analyzer.
3. Press the PRESET key in the SYSTEM keypad to perform a factory preset of the
analyzer.
The analyzer is now set to its default state. The default measured quantity is the transmission S-parameter S21. This quantity is zero in the current test setup, so the trace
shows the noise level.
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Performing a Reflection Measurement
Press the TRACE SELECT key in the TRACE keypad and use the softkeys in the
"Trace Select" menu if you wish to create a new trace or a new diagram area.
2.1.2 Parameter and Sweep Range Selection
After preset the display shows a diagram with a dB Mag scale. The sweep range (scale
of the horizontal axis) is equal to the maximum frequency range of the analyzer, and
the S-parameter S21 is selected as a measurement parameter.
To obtain information about the reflection characteristics of your DUT you have to
select an appropriate measurement parameter and specify the sweep range.
1. In the CHANNEL keypad, press START CENTER and enter the lowest frequency
you want to measure in the "Start Frequency" numeric entry bar (e.g. 5 GHz).
Note: If you use the DATA ENTRY keys at the front panel for data entry, simply
type 5 and terminate the entry with the G/n key. Refer to section "Data Entry" to
learn more about entering numeric values and characters.
2. Press STOP SPAN and enter the highest frequency you want to measure in the
"Stop Frequency" numeric entry bar (e.g. 5.5 GHz).
3. In the TRACE keypad, press MEAS and select the forward reflection coefficient S
as a measurement parameter.
11
4. In the TRACE keypad, press SCALE and activate the "Autoscale" function. The
analyzer adjusts the scale of the diagram to fit in the entire S11 trace, leaving an
appropriate display margin.
Tip: Refer to chapter 2.3.3, "Scaling Diagrams", on page 41 to learn more about
the different methods and tools for diagram scaling.
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Performing a Reflection Measurement
2.1.3 Instrument Calibration
The analyzer provides a wide range of sophisticated calibration methods for all types of
measurements. Which calibration method is selected depends on the expected system
errors, the accuracy requirements of the measurement, on the test setup and on the
types of calibration standards available.
In the following we assume that the calibration kit R&S ZV-Z21 contains an appropriate
male short standard with known physical properties. With a single short standard, it is
possible to perform a normalization, compensating for a frequency-dependent attenuation and phase shift in the signal path.
Due to the analyzer's calibration wizard, calibration is a straightforward, menu-guided
process.
1. Unscrew the DUT and connect the male short standard from calibration kit R&S
ZV-Z21.
2. In the CHANNEL keypad, press CAL to open the calibration menu.
3. Activate "Start Cal – One Port P1 – Normalization (Short)" to open the calibration
wizard for the selected calibration type.
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Performing a Reflection Measurement
4. In the first dialog of the wizard, select the calibration kit (here: "ZV-Z21") and the
test port connector (here: N 50 Ω (f), corresponding to a male calibration standard),
and click "Next".
The next dialog of the calibration wizard shows that only a single calibration standard needs to be measured.
5. Click the box "Short (m)..." to initiate the measurement of the connected short
standard.
The analyzer performs a calibration sweep and displays a message box with a progress bar. After completing the sweep the analyzer generates a short sound and a
green checkmark appears in the checkbox.
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Performing a Reflection Measurement
6. Click "Apply" to close the wizard, calculate and store the system error correction
data and apply them to the current measurement.
7. Remove the short standard and connect the DUT again.
2.1.4 Evaluation of Data
The analyzer provides various tools to optimize the display and analyze the measurement data. For instance, you can use markers determine the maximum of the reflection
coefficient, and change the display format to obtain information about the phase shift of
the reflected wave and the impedance of your DUT.
1. In the TRACE keypad, press MARKER. This places "Marker 1" to its default position (center of the sweep range).
A marker symbol (triangle) appears on the trace. The stimulus value (frequency)
and response value (magnitude of the reflection coefficient converted to a dB
value) at the marker position is displayed in the marker info field in the upper right
corner of the diagram.
2. Press MARKER FUNCT and activate "Min Search".
The marker jumps to the absolute minimum of the curve in the entire sweep range.
The marker info field shows the coordinates of the new marker position.
3. In the TRACE keypad, press FORMAT and select the "Phase" of the reflection
coefficient to be displayed.
The phase is shown in a Cartesian diagram with a default vertical scale of 225 deg
to +225 deg. The marker info field shows the frequency and phase at the marker
position.
4. Still in the FORMAT menu, select "Smith".
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Performing a Reflection Measurement
The Smith chart shows lines of constant real and imaginary part of the impedance
in the reflection coefficient plane.
Tip: Refer to section chapter 3.2.4, "Display Formats and Diagram Types",
on page 67 to learn more about the diagram properties.
2.1.5 Saving and Printing Data
The analyzer provides standard functions for saving measurement settings and for
printing the results. You can use these functions as if you were working on a standard
PC. Moreover you can export your trace data to an ASCII file and reuse it in a later
session or in an external application.
Data transfer is made easier if external accessories are connected to the analyzer or if
the instrument is integrated into a LAN. Refer to Connecting External Accessories and
chapter 1.7, "Connecting to a LAN", on page 25 to obtain information about the neces-
sary steps.
1. Press TRACE FUNCT and activate "Import/Export – Data Export".
2. In the "Export Data" dialog opened, select a file location, format and name and activate "Save".
The active trace data is written to an ASCII file.
3. Press PRINT in the SYSTEM keypad and select "Print Now" to create a hardcopy
of your diagram.
4. Select "Print to File..." or "Print to Clipboard" to copy the diagram to a file or an
external application.
5. Press SAVE in the SYSTEM keypad.
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Performing a Transmission Measurement
6. In the "Save As" dialog opened, select a file location, format and name and activate
"Save".
The active setup is stored to a file and can be reused in a later session.
Proceed as described in chapter 1.4, "Starting the Analyzer and Shutting Down",
on page 22 to shut down your analyzer.
2.2 Performing a Transmission Measurement
A transmission measurement involves the same steps as a reflection measurement.
Note the following differences:
●
The test setup for transmission measurements involves two or more DUT and analyzer ports. For a two-port transmission measurement, you can connect the input of
your DUT to port 1 of the analyzer, the output to port 2. After a preset, the analyzer
will measure the forward transmission S-parameter S21.
●
The analyzer provides special calibration types for transmission measurements.
Use the calibration wizard and select an appropriate type. A TOSM calibration will
correct the system errors for all transmission and reflection S-parameters.
●
The S-parameter wizard ("System – Measurement Wizard – S-parameter" wizard)
will guide you through the essential steps of a standard transmission measurement.
2.3 Basic Tasks
The following sections describe how to solve basic tasks that you will frequently
encounter when working with the instrument. In particular you can learn how to access
instrument functions and control dialogs without a mouse and keyboard.
2.3.1 Control via Front Panel Keys
Although a mouse and external keyboard simplify the operation of the instrument, you
can access all essential functions using the keys on the front panel. The following
examples are intended to make you familiar with front panel key operation.
To access a particular menu command ...
1. Press the MENU key in the SUPPORT keypad to access the menu bar and open
the "File" menu.
2. Use the keys in the NAVIGATION keypad or the rotary knob to navigate between
and within the menus.
● Use the "Cursor Left" and "Cursor Right" keys to change between the different
menus in the menu bar. When the first option in a pull-down menu is a sub-
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menu, the submenu will be opened first before proceeding to the next option in
the menu bar.
● Use the "Cursor Up" and "Cursor Down" keys and the rotary knob (if rotated) to
scroll up and down in a menu.
● OK ENTER and the rotary knob (if pressed) expand a submenu, open a dialog,
or initiate an action, depending on the selected command type.
● CANCEL ESC compresses the current submenu and moves the cursor one
menu level up or closes the active dialog, depending on the selected softkey
type.
3. As soon as you reach the desired menu command (which must not be one opening
a submenu) press OK ENTER or press the rotary knob to initiate an action or open
a dialog.
After command execution or after closing the dialog, the menu bar is deactivated
and the cursor returns to the diagram/softkey area.
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To make a selection in a dialog...
1. Press a softkey with three dots to open a dialog.
2. Use the keys in the NAVIGATION keypad and the rotary knob to access the controls in the dialog.
● Press "Left Field" or "Right Field" to switch between the control elements in a
dialog.
3. ● Press the cursor keys or turn the rotary knob to switch between several entries
in a list of alternative or independent settings.
4. Use the DATA ENTRY keys or the rotary knob to enter characters and numbers.
For more details refer to section "Data Entry" below.
5. Press OK ENTER, CANCEL ESC or press the rotary knob to close the active dialog.
2.3.2 Data Entry
The analyzer provides dialogs with various types of input fields where you can enter
numeric values and character data. Data entry with a mouse and an external keyboard
is a standard procedure known from other Windows applications. However, there are
various alternative ways to enter data.
2.3.2.1 Using Front Panel Keys
If no mouse and no external keyboard is connected to the analyzer, you can use the
keys in the DATA ENTRY keypad to enter numbers, units, and characters.
To enter a numeric value
1. Place the cursor into a numeric data input field in a dialog or in the numeric entry
bar.
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2. Press the DATA ENTRY keys.
● Use 0 to 9 to enter the corresponding numbers.
● Use . and - to enter a decimal point or change the sign of the value.
● Use . G/n, M/μ, k/m, or x1 to multiply the entered value with factors of 10(-)9,
10(-)6, 10(-)3 or 1 and add the appropriate physical unit.
To enter a character string
1. Place the cursor into a character data input field in a dialog.
2. Press the DATA ENTRY keys as if you were writing a short message on your
mobile phone.
● Press 0 to 9 once to enter the corresponding numbers.
● Press the keys repeatedly to select one of the other characters assigned to the
key.
● Wait 2 seconds to confirm an entry.
● Use . or to enter a dot or a hyphen.
● Use the sign key to change from upper case to lower case and vice versa.
● Use G/n, M/μ, or k/m to enter the letters G, M or K (case-insensitive).
● Use the BACK key to correct wrong entries, deleting the character to the left of
the current cursor position.
● Press OK ENTER to complete an entry.
● Press ESC CANCEL to close the popup dialog, discarding the entries made.
3. To enter letters other than G, M or K, you can also use one of the following methods:
● Turn the rotary knob until the desired letter appears in the character input field.
●
If the active input field has a
symbol, then use the analyzer's on-screen key-
board.
● Otherwise, use a mouse and Windows XP's on-screen keyboard.
2.3.2.2 Using the Analyzer's On-Screen Keyboard
The on-screen keyboard allows you to enter characters, in particular letters, without an
external keyboard. It is available for all character input fields which have a
Operation with front panel keys
1. Place the cursor into a character data input field in a dialog or in the numeric entry
bar.
2.
Press OK or the key in the NAVIGATION keypad to open the on-screen keyboard.
3. Use the cursor keys in the NAVIGATION keypad or turn the rotary knob to move
the cursor to a character.
symbol.
4. Press OK ENTER or the rotary knob to select the character for the input string.
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5.
After completing the input string use the key to move to the OK button.
6. Press OK ENTER or the rotary knob to apply your selection and close the keyboard.
Operation with a mouse
1.
Click the symbol to open the on-screen keyboard.
2. Click a sequence of characters and OK to apply your selection and close the keyboard.
2.3.2.3
Using the Windows® On-Screen Keyboard
The Windows On-Screen Keyboard allows you to enter characters, in particular letters,
even if an input field cannot call up the analyzer's own on-screen keyboard. Examples
of such fields are the input fields in the "Index" and "Search" tabs of the Help system. A
mouse is required for using the On-Screen Keyboard.
To call up the on-screen keyboard,
1. Press the Windows key in the SUPPORT keypad to access Windows and open the
start menu.
2. Select "All Programs – Accessories – Accessibility (Win XP) | Ease of Access (Win
7) – On-Screen Keyboard".
The "System – External Tools" submenu contains a shortcut to the Windows on-screen
keyboard. Simply click "Mouse Keyboard.lnk" to open the keyboard.
2.3.3 Scaling Diagrams
The analyzer provides several alternative tools for setting the sweep range and customizing the diagrams. Pick the method that is most convenient for you.
2.3.3.1 Setting the Sweep Range
The sweep range for all channels is displayed in the channel list across the bottom of
the diagram area:
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To change the sweep range, use one of the following methods:
●
Press the START CENTER or STOP SPAN keys in the CHANNEL keypad.
●
Right-click the start or stop value in the channel list and select "Start", "Stop", "Center", "Span" from the context menu.
●
Select "Start", "Stop", "Center", "Span" from the "Channel Stimulus" menu.
●
Use the marker functions (MARKER FUNCT key).
2.3.3.2 Reference Value and Position
The analyzer provides three parameters for changing the scale of the vertical
(response) axis:
●
Changing the "Reference Value" or "Reference Position" shifts the trace in vertical
direction and adjusts the labels of the vertical axis. "Reference Value" also works
for radial diagrams.
●
Changing the "Scale/Div." modifies the value of the vertical or radial diagram divisions and thus the entire range of response values displayed.
The "Scale/Div." and the "Reference Value" is indicated in the scale section of the
trace list.
To change one of the parameters use one of the following methods:
●
Press the SCALE key in the TRACE keypad.
●
Right-click the scale section in the trace list and select the parameters from the
context menu.
●
Select the parameters from the "Trace Scale" menu.
●
Use the marker functions (MARKER FUNCT key).
2.3.3.3 Autoscale
The "Autoscale" function adjusts the scale divisions and the reference value so that the
entire trace fits into the diagram area. To access "Autoscale", use one of the following
methods:
●
Press the SCALE key in the TRACE keypad.
●
Right-click the scale section in the trace list and select "Autoscale" from the context
menu.
●
Select "Autoscale" from the "Trace – Scale" menu.
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2.3.3.4 Circular Diagrams
The radial scale of a circular ("Polar", "Smith" or "Inverted Smith") diagram can be
changed with a single linear parameter, the "Reference Value". The reference value
defines the radius of the outer circumference.
●
Increasing the "Reference Value" scales down the polar diagram.
●
Decreasing the "Reference Value" magnifies the polar diagram.
The "Reference Value" is indicated in the scale section of the trace list.
To change the "Reference Value" use one of the following methods:
●
Press the SCALE key in the TRACE keypad
●
Right-click the scale section in the trace list and select the parameter from the context menu.
●
Select the parameter from the "Trace – Scale" menu.
●
Use the marker functions.
The "Autoscale" function also works for polar diagrams.
2.3.3.5 Using Marker Functions
Marker functions are a convenient tool for scaling (in particular: magnifying) diagrams
without entering explicit numeric values. You simply place a marker to a trace point
and use the marker values to change the sweep range or move the trace relative to the
vertical axis. A mouse makes it easier to activate (click) or move (drag and drop) markers.
To set the sweep range use one of the following methods:
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Define "Start" and "Stop" values
1. Create two normal markers, e.g. the markers Mkr 1 and Mkr 2, and place them to
the desired start and stop values of the sweep range.
2. Activate "M 1" and click "Trace – Marker Funct. – Start = Marker".
3. Activate "M 2" and click "Trace – Marker Funct. – Stop = Marker".
Use a definite "Span"
1. Create a marker and set it to delta mode.
The analyzer automatically creates a reference marker in addition to the delta
marker.
2. Place the reference marker to the desired start value of the sweep range.
3. Set the value of the delta marker equal to the desired (positive or negative) span.
4. Activate the delta marker and click "Trace – Marker Funct. – Span = Marker".
To move the trace relative to the vertical axis proceed as follows:
1. Create a normal marker, e.g. the marker "M 1", and place it to a particular trace
point. E.g. you can use the marker "Search" functions to locate a maximum or minimum on the trace.
2. Click "Trace – Marker Funct. – Max = Marker" to move the trace towards the upper
diagram edge, leaving the values of the vertical divisions ("Scale Div.") and the
overall vertical scale unchanged. Analogously, click "Min = Marker" to move the
trace towards the lower diagram edge, or click "Ref Value = Marker" to move the
trace towards the "Reference Value".
2.3.3.6 Enlarging the Diagram Area
The analyzer provides different tools for customizing the contents and size of the diagram areas:
●
"Maximize" allows you to enlarge the active diagram area to occupy the whole window. A double-click on any point in the diagram area is equivalent to the "Maximize" function.
●
The "Title", the "Softkey Labels", the "Status Bar" and the "Hardkey Bar" are
optional display elements which you can hide in order to gain space for the diagram.
●
Use the context menu of the diagram area, the keys in the DISPLAY keypad bar or
the "Display" menu to access the scaling functions above.
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3 System Overview
The following chapter provides an overview of the analyzer's capabilities and their use.
This includes a description of the basic concepts that the analyzer uses to organize,
process and display measurement data, of the screen contents, possible measured
quantities, calibration methods and typical test setups.
For a systematic explanation of all menus, functions and parameters and background
information refer to the reference description on the graphical user interface (GUI Reference) in your analyzer's help system.
3.1 Basic Concepts
The analyzer provides a variety of functions to perform a particular measurement and
to customize and optimize the evaluation of results. To ensure that the instrument
resources are easily accessible and that user-defined configurations can be conveniently implemented, stored and reused the instrument uses a hierarchy of structures:
●
Global resources can be used for all measurements, irrespective of the current
measurement session or setup.
●
A setup comprises a set of diagram areas with all displayed information that can be
stored to a setup file.
●
The diagram areas show traces which are assigned to channels. See chap-
ter 3.1.3, "Traces, Channels and Diagram Areas", on page 46.
3.1.1 Global Resources
The analyzer provides global settings that are mostly hardware-related and can be
used for all measurements, irrespective of the current measurement session or setup.
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The settings are stored in independent files and do not enter into any of the setup files.
The following settings correspond to global resources:
●
Calibration kits
●
Connector types
●
Cal pool data including system error correction and power correction data
●
Color schemes
The data related to global resources are not affected by a "Preset" of the analyzer.
However, it is possible to delete or reset global resource data using the "Resets" tab in
the "System Config" dialog.
3.1.2 Setups
A setup comprises a set of diagram areas with all displayed information that can be
stored to a NWA setup file (*.zvx) and reused. Each setup is displayed in an independent window. The setup file contains the following information:
●
General settings related to the setup
●
The trace settings for all traces in the diagram areas
●
The channel settings for all channels associated to the traces
●
The display settings for each diagram area
The "File" menu is used to organize setups.
In the "System – External Tools" submenu, you can find demo setups *.vbs for various measurement scenarios. You can modify the demo setups and store them to a
*.zvx file for later use. Moreover the "S-Parameter Wizard" provides predefined, optimized setup s for many measurements.
3.1.3 Traces, Channels and Diagram Areas
The analyzer arranges, displays or stores the measured data in traces which are
assigned to channels and displayed in diagram areas. To understand the menu structure of the instrument and quickly find the appropriate settings, it is important to understand the exact meaning of the three terms.
●
A trace is a set of data points that can be displayed together in a diagram area.
The trace settings specify the mathematical operations used in order to obtain
traces from the measured or stored data and to display them.
●
A channel contains hardware-related settings to specify how the network analyzer
collects data.
●
A diagram area is a rectangular portion of the screen used to display traces. Diagram areas belonging to the same setup are arranged in a common window. The
settings for diagram areas are described in chapter 3.2.2, "Display Elements in the
Diagram Area", on page 55.
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A diagram area can contain a practically unlimited number of traces, assigned to different channels. Diagram areas and channels are completely independent from each
other.
3.1.3.1 Trace Settings
The trace settings specify the mathematical operations used in order to obtain traces
from the measured or stored data. They can be divided into several main groups:
●
Selection of the measured quantity (S-parameters, wave quantities, ratios, impedances,...)
●
Conversion into the appropriate display format and selection of the diagram type
●
Scaling of the diagram and selection of the traces associated to the same channel
●
Readout and search of particular values on the trace by means of markers
●
Limit check
The "Trace" menu provides all trace settings. They complement the definitions of the
"Channel" menu. Each trace is assigned to a channel. The channel settings apply to all
traces assigned to the channel.
If a trace is selected in order to apply the trace settings, it becomes the active trace. In
manual control there is always exactly one active trace, irrespective of the number of
channels and traces defined. The active channel contains the active trace. In remote
control, each channel contains an active trace; refer to the relevant sections in your
analyzer's help system.
3.1.3.2 Channel Settings
A channel contains hardware-related settings to specify how the network analyzer collects data. The channel settings can be divided into three main groups:
●
Control of the measurement process ("Sweep", "Trigger", "Average")
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●
Description of the test setup ("Power" of the internal source, IF filter "Bandwidth"
and "Step Attenuators", "Port Configuration")
●
Correction data ("Calibration", "Offset")
The "Channel" menu provides all channel settings.
After changing the channel settings or selecting another measured quantity, the analyzer needs some time to initialize the new sweep. This preparation period increases
with the number of points and the number of partial measurements involved. It is
visualized by a "Preparing Sweep" symbol in the status bar: All analyzer settings can
still be changed during sweep initialization. If necessary, the analyzer terminates the
current initialization and starts a new preparation period. During the first sweep after a
change of the channel settings, an additional red asterisk symbol appears in the status
bar:
All analyzer settings can still be changed during sweep initialization. If necessary, the
analyzer terminates the current initialization and starts a new preparation period. During the first sweep after a change of the channel settings, an additional red asterisk
symbol appears in the status bar:
3.1.4 Data Flow
The analyzer processes the raw measurement data in a sequence of stages in order to
obtain the displayed trace. The following diagram gives an overview.
The diagram consists of an upper and a lower part, corresponding to the data processing stages for the entire channel and for the individual traces. All stages in the diagram
are configurable. Note that the channel data flow for S-parameters (and quantities
derived from S-parameters such as impedances, admittances, stability factors etc.) differs from the channel data flow for wave quantities (and derived quantities such as
ratios, PAE etc.).
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3.2 Screen Elements
This section describes the operating concept of the network analyzer, including the
alternative navigation tools for mouse and hardkey operation, the trace settings, markers and diagram areas. For a description of the different quantities measured by the
analyzer refer to chapter 3.3, "Measured Quantities", on page 75.
3.2.1 Navigation Tools of the Screen
The main window of the analyzer provides all control elements for the measurements
and contains the diagram areas for the results. There are several alternative ways to
access an instrument function:
●
Using the menus and submenus of the menu bar (provides all settings)
●
Using the softkeys of the softkey bar (alternative to the previous method)
●
Using the hardkey bar (preselection of the most important menus)
For further reference:
●
Refer to chapter 3.2.2, "Display Elements in the Diagram Area", on page 55 to
obtain information about the results in the diagram area.
●
Refer to section "Display Menu" in the reference chapter of your analyzer's Help
system and learn how to customize the screen.
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3.2.1.1 Menu Bar
All analyzer functions are arranged in drop-down menus. The menu bar is located
across the top of the diagram area:
Menus can be controlled in different ways:
●
With a mouse, like the menus in any Windows application. A left mouse click
expands a menu or submenu. If a menu command has no submenu assigned, a
left mouse click opens a dialog or directly activates the menu command.
●
Using the front panel keys.
●
With a combination of the previous methods, using the hardkey bar (front panel key
bar, activated via Display – Config./View).
The active menu is the menu containing the last executed command. If the softkey bar
or hardkey bar is displayed ("Display – Config./View – Softkey Labels: On"), then the
active menu is indicated on top of the softkey/hardkey bar.
When you select a command in a new menu the softkey bar is updated to reflect the
new active menu with all commands. You can continue operation using the softkeys.
Overview of menu functions
●
The "Control"
●
The "File" menu provides standard Windows functions to create, save, recall or
menu provide standard Windows functions to control windows.
print setups, to copy the current screen and to shut down the application.
●
The "Trace" menu provides all trace settings and the functions to create, select,
modify and store different traces. In addition the menu provides the marker, search
and limit check functions.
●
The "Channel" menu provides all channel settings and the functions to create,
select, modify and store different channels.
●
The "Display" menu provides all display settings and the functions to create, select,
modify and arrange different diagram areas.
●
The "System" menu provides functions to reverse operations, return to a defined
instrument state, retrieve information on the instrument and access service functions. Besides, it configures the remote control operation, starts the "Measurement
Wizard" and provides print options.
●
The "Window" menu provides standard Windows functions to arrange different windows on the screen.
●
The "Info" menu provides information and selftest options for service purposes and
troubleshooting.
●
The "Help" menu provides assistance with the network analyzer and its operation.
3.2.1.2 Menu Structure
All menus show an analogous structure.
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●
A menu command with a right arrow expands a submenu with further related settings.
Example: "Measure" expands a submenu to select the quantity to be measured
and displayed.
●
A menu command with three dots appended calls up a dialog providing several
related settings.
Example: "More S-Parameters..." opens a dialog to select S-parameters for multiport measurements or mixed mode S-parameters.
●
A menu command with no arrow or dots directly initiates an action.
Example: "S21" selects the forward transmission coefficient S21 as measured
quantity.
●
A dot preceding the menu command indicates the current selection in a list of alternative settings.
Example: In the figure above, S21 is selected as measured quantity.
3.2.1.3 Softkey Bar
The softkey bar displays the commands of the active menu so that they can be activated by hitting the associated keys on the front panel.
It consists of three elements:
●
Heading
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The heading shows the two lowest level menu commands in the current branch of
the menu tree. The lowest-level command appears on a shaded background.
●
Function softkeys
Up to 8 softkeys, each corresponding to a command of the active menu. The function of the softkeys and their labels are strictly equivalent to the corresponding
menu commands.
– A large dot in the lower right corner indicates the current selection in a list of
alternative settings.
– Three dots indicate that the softkey calls up a dialog providing several related
settings.
– A right arrow indicates a submenu with further related settings.
– A softkey with no arrow or dots directly initiates an action.
●
Navigation softkey (optional)
Softkey no. 8 or softkeys no. 7 and no. 8 are reserved for navigation:
– More ½ and More 2/2 toggle between two groups of softkeys which belong to
the same menu. The softkeys are provided whenever the active menu contains
more than 7 commands.
– Menu Up activates the higher-level menu and is provided in all menus except
the top-level one listing the main menus in the menu bar.
The softkey bar is automatically updated when the active menu is changed.
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You can hide the softkey bar and gain screen space for the diagram areas if you use a
mouse to control the analyzer ("Display – Config./View"). All settings are accessible
from the menus listed in the menu bar across the top of the screen.
Moreover, you don't have to display the softkey bar permanently in order to make use
of its functionality. Hitting any of the keys associated to the softkey bar will make it visible for a period of time sufficient to select the next instrument function.
3.2.1.4 Hardkey Bar
The hardkey bar (front panel key bar, "Display – Config./View") represents the most
commonly used front panel keys of the analyzer. Clicking a key symbol executes the
action of the corresponding key.
The hardkey bar corresponds to the TRACE, CHANNEL, DISPLAY and SYSTEM keypads:
The hardkey bar provides access to the basic groups of settings with a single mouse
click. It is particularly useful if the analyzer is controlled from an external monitor or
Remote Desktop. Alternatively the settings are accessible from the menus of the menu
bar or from the softkey bar.
The hardkey bar is hidden by default to gain screen space for the diagram areas.
3.2.1.5 Status Bar
The status bar (Display – Config./View) shows
●
the statistics for the sweep average (if sweep average is on)
●
an "Ext Ref" section if the analyzer is configured to use an External Reference
clock
●
the progress of the sweep
●
the LXI status (if LXI is enabled)
●
the error log opener icon (if the error log is non-empty) and
●
the control mode of the analyzer (LOCAL or REMOTE)
If LXI is enabled, a green LXI status symbol indicates that a LAN connection has been
established; a red symbol indicates that no LAN cable is connected.
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During sweep initialization, the progress bar for the sweep is replaced by a
symbol. During the first sweep after a change of the channel settings, an
additional red asterisk symbol appears:
You can hide the status bar and gain screen space for the diagram areas.
3.2.2 Display Elements in the Diagram Area
The central part of the screen is occupied by one or several diagram areas.
A "diagram area" is a rectangular portion of the screen used to display traces. Diagram
areas are arranged in windows; they are independent of trace and channel settings. A
diagram area can contain a practically unlimited number of traces, assigned to different
channels (overlay mode).
Diagram areas are controlled and configured by means of the functions in the "Display"
menu and the following additional settings:
●
The settings in the "Window" menu arrange several windows containing one or
more diagram areas within the entire screen. Each window corresponds to a setup.
Only one setup can be active at a time, and only the traces of the active setup are
updated by the current measurements.
●
Various settings to assign traces to diagram areas are provided in the "Trace –
Traces" submenu.
Diagram areas may contain:
●
Measurement results, in particular the traces and marker values
●
An indication of the basic channel and trace settings
●
Context menus providing settings related to the current screen
●
Error messages
The examples in this section have been taken from Cartesian diagrams. All other diagram types provide the same display elements.
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3.2.2.1 Title
Across the top of the diagram area, an optional title describes the contents of the area.
Different areas within a setup are distinguished by area numbers in the upper right corner.
Use the context menu or the functions in the "Display" menu to display, hide or change
the title and to add and customize diagram areas.
3.2.2.2 Traces
A trace is a set of data points displayed together in the diagram area. The individual
data points are connected so that each trace forms a continuous line.
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The trace can be complemented by the following display elements, plotted with the
same color:
●
Reference value (for all traces): The reference value is indicated with a triangle at
the right edge of the diagram and a dashed, horizontal line. The value and position
of the triangle can be changed in order to modify the diagram scale and shift the
trace vertically.
●
Measured quantity (for the active trace): The measured quantity is indicated in the
left upper corner of the diagram.
A trace can be either a data trace, a memory trace, or a mathematical trace; see
"Trace Types" on page 57.
A right mouse click on any point of the diagram area (except the marker info field and
the measured quantity info) opens a context menu:
The settings correspond to the most common commands in the "Display – Area Select"
and "Display – Config View" menus.
Trace Types
The analyzer uses traces to display the current measurement result in a diagram area
but is also capable of storing traces to the memory, recalling stored traces, and defining mathematical relations between different traces. There are three basic trace types:
●
Data traces show the current measurement data and are continuously updated as
the measurement goes on. Data traces are dynamic traces.
●
Memory traces are generated by storing the data trace to the memory. They represent the state of the data trace at the moment when it was stored. Memory traces
are static traces which can be stored to a file and recalled.
●
Mathematical traces are calculated according to a mathematical relation between
constants and the data or memory traces of the active setup. A mathematical trace
that is based on the active data trace is dynamic.
It is possible to generate an unlimited number of memory traces from a data trace and
display them together. Markers and marker functions are available for all trace types.
The trace type of each trace in a diagram area is indicated in the trace list. You can
also make each trace "Invisible" without deleting it.
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Trace List and Trace Settings
The main properties of all traces assigned to the diagram area are displayed in the
trace list in the upper left corner.
Each line in the trace list describes a single trace. The active trace is highlighted. The
lines are divided into several sections with the following contents (from left to right):
●
The trace name appears in the first section. The default names for new traces are
Trc<n> where <n> is a current number. A "Mem..." preceding the trace name indicates a memory trace. Right-click the section and call the "Trace Manager" from
the context menu to change the trace name.
●
The measured quantity (e.g. an S-parameter or a ratio) appears on a colored
background. The measured quantity of the active trace is also displayed in the diagram area below the trace list.
●
The format section shows how the measured data is presented in the graphical
display ("Trace – Format").
●
The next sections show the value of the vertical or radial diagram divisions ("Scale
Div.") and the reference value ("Ref").
●
The channel section shows the channel that each trace is assigned to. It is omitted
if the all traces in the diagram area are assigned to the same channel.
●
The type section indicates "Invisible" if a trace is hidden. Otherwise it indicates
– "Math", if the trace is a mathematical trace
– "GAT", if a time gate is active for the trace
– "ALC", if the drive port is under automatic level control
Right-click the trace name and click "Show Data" or "Show Mem" from the context
menu to display and hide data and memory traces. Use the "Trace Funct(ions)" to
define mathematical traces.
Right-click any of the sections in the trace list (except the type section) to open a context menu and access the most common tasks related to the section.
A right mouse click on the trace name, the measured quantity, and the format and
scale section of the trace list opens the following context menus, respectively:
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The settings correspond to the most common commands in the "Trace – Trace Select",
"Trace – Trace Funct", "Trace – Meas", "Trace – Format" and "Trace – Scale" menus.
A red label "Cal Off !" appears behind the trace list if the system error correction no
longer applies to one or more traces.
3.2.2.3 Markers
Markers are tools for selecting points on the trace and for numerical readout of measured data. The analyzer provides three different basic marker types.
●
A (normal) marker ("Mkr 1, Mkr 2, ...") determines the coordinates of a measurement point on the trace. Up to 10 different normal markers can be assigned to a
trace.
●
A reference marker ("Ref") defines the reference value for all delta markers.
●
A delta marker ("Δ") indicates the coordinates relative to the reference marker.
●
The stimulus value of a discrete marker always coincides with a sweep point so
that the marker does not show interpolated measurement values.
The markers 1 to 4 are also used for bandfilter search mode. The examples below
show a bandpass search and a bandstop search, respectively.
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●
"Mkr 1" indicates the maximum (minimum) of the peak.
●
"Mkr 2" and "Mkr 3" indicate the lower and upper band edge where the trace value
has decreased (increased) by a definite "Level" value.
●
"Mkr 4" indicates the center of the peak, calculated as the arithmetic mean value of
the LBE and UBE positions.
The "Paste Marker List" allows you to select marker values as numeric entries; see
chapter 3.2.3.4, "Paste Marker List", on page 66.
Marker Info Field
The coordinates of all markers defined in a diagram area are displayed in the info field,
which by default is located in the upper right corner.
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The list contains the following information:
●
"Mkr 1, Mkr 2, ..." denote the marker numbers. Markers are displayed with the
same color as the associated trace.
●
The marker coordinates are expressed in one of the marker formats selected via
"Marker – Format". The formats of the markers assigned to a trace are independent
of each other and of the trace format settings.
●
The active marker has a dot placed in front of the marker line.
●
A "Δ" sign placed in front of the marker line indicates that the marker is in delta
mode.
Customizing the marker info field
To change the position, appearance or contents of the marker info field use one of the
following methods:
●
Double-click the info field to open the "Mkr Properties" dialog with extended settings for all markers of the active trace. Select the options in the "Show Info" panel
to customize the information in the info field ("Active Trace Only", "Stimulus Info
Off").
●
Right-click the info field to open a context menu providing frequently used marker
settings.
●
To change the position of the marker info field, select "Movable Marker" Info from
the context menu. Drag-and-drop the info field to any position in the active diagram
area.
●
To change the format of the active marker, select "Mkr Format".
●
To express the coordinates of the active marker relative to the reference marker,
activate the Delta Mode.
For more information: Show Info Table
In addition to the marker info field, the analyzer provides an info table with extended
marker information.
The table is hidden by default. To display the table double-click the marker info field to
open the "Marker Properties" dialog.
A right mouse click on the marker info field opens a context menu:
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"Movable Marker Info" allows the marker info field to be placed to any position in the
diagram area. The remaining settings correspond to the most common commands in
the "Trace – Marker" and "Trace – Search" menus.
3.2.2.4 Channel Settings
The main properties of all channels assigned to the traces in the diagram area are displayed in the channel list below the diagram.
Each line in the channel list describes a single channel. The channel of the active trace
is highlighted. The lines are divided into several sections with the following contents
(from left to right):
Each line in the channel list describes a single channel. The channel of the active trace
is highlighted. The lines are divided into several sections with the following contents
(from left to right):
●
The channel name appears in the first section. The default names for new channels are Ch<n> where <n> is a current number. Right-click the section and call the
"Channel Manager" from the context menu to change the channel name.
●
The measurement mode identifier section (optional) indicates a special test
mode of the channel, e.g. the measurement of a 2nd harmonic ("H2"), a 3rd harmonic ("H3"), or the mixer mode ("Mix") or an arbitrary frequency conversion mode
("Arb").
●
The stimulus axis section shows the frequency or power stimulus axis currently
selected in the "Channel Mode > Port Configuration > Stimulus" dialog. "fb"
denotes the channel base frequency; "Pb" the channel base power; "P 1" the port 1
source frequency or power, "Gen 1" an external generator source frequency or
power, "Rec" the receiver frequency (all ports).
This information is particularly valuable if different port frequencies and powers are
specified (with option R&S ZVA-K4).
●
Start indicates the lowest value of the sweep variable (e.g. the lowest frequency
measured), corresponding to the left edge of the Cartesian diagram.
●
The color legend shows the display color of all traces assigned to the channel.
The colors are different, so the number of colors is equal to the numbers of traces
assigned to the channel.
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●
The value behind the color legend shows the constant stimulus value, which is
either the power of the internal signal source (for frequency sweeps and time
sweeps) or the CW frequency (for power sweeps). "fb" denotes the channel base
frequency; "Pb" the channel base power.
●
Stop indicates the highest value of the sweep variable (e.g. the highest frequency
measured), corresponding to the right edge of the Cartesian diagram.
Right-click any of the sections in the trace list (except the color legend) to open a context menu and access the most common tasks related to the section.
A right mouse click on the channel name, the sweep range, and the additional parameter section of the channel list opens the following context menus, respectively:
The settings correspond to the most common commands in the "Channel – Channel
Select", "Channel – Stimulus" and "Channel – Power Bandwidth Average" menus.
3.2.2.5 Context Menus
To provide access to the most common tasks and speed up the operation, the analyzer
offers context menus (right-click menus) for the following display elements:
●
Diagram area
●
Marker info field
●
Trace list (separate context menus for trace name section, measured quantity section, format section, scale section, and channel section)
●
Channel list (separate context menus for channel name section, sweep range section, additional parameter section)
Working with context menus requires a mouse. Click inside the display element that
you want to work with using the right mouse button.
Except from some particular screen configurations, anything you can do from a context
menu you can also do from the menu bar or using front panel keys and softkeys. Use
whatever method is most convenient for you.
3.2.3 Dialogs
Dialogs provide groups of related settings and allow to make selections and enter data
in an organized way. All softkeys with three dots behind their labeling (as in "Marker
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Properties...") call up a dialog. The dialogs of the analyzer have an analogous structure
and a number of common control elements.
The "Dialog Transparency" function in the "System Config" menu varies the transparency of all dialogs. With an appropriate setting, you can control the dialogs and at the
same time view the underlying traces and display elements.
We assume that you are familiar with standard Windows dialogs and mouse operation.
Refer to chapter 2.3.1, "Control via Front Panel Keys", on page 37 to learn how to control dialogs without a mouse and keyboard.
3.2.3.1 Immediate vs. Confirmed Settings
In some dialogs, the settings take effect immediately so that the effect on the measurement is observable while the dialog is still open. This is especially convenient when a
numeric value is incremented or decremented, e.g. via the rotary knob.
In most dialogs, however, it is possible to cancel an erroneous input before it takes
effect. The settings in such dialogs must be confirmed explicitly.
The two types of dialogs are easy to distinguish:
●
Dialogs with immediate settings provide a "Close" button but no "OK" button.
Example: "Step Size" dialog.
●
Dialogs with confirmed settings provide both an "OK" button and a "Cancel" button.
Example: On-screen keyboard.
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You can also cancel an immediate setting using "System – Undo"!.
3.2.3.2 On-Screen Keyboard
A keyboard symbol next to a character input field opens the analyzer's on-screen
keyboard.
The on-screen keyboard contains two sets of characters plus the following additional
controls:
●
"Shift" changes between the two character sets containing lower case letters/
numbers and upper case letters/special characters, respectively.
●
"<= BS" deletes the current string in the alphanumeric input field.
●
"OK" applies the current selection and closes the keyboard. The current string is
written into the input field of the calling dialog. See also chapter 3.2.3.1, "Immedi-
ate vs. Confirmed Settings", on page 64.
●
"Cancel" discards the current selection and closes the keyboard. The input field of
the calling dialog is left unchanged.
The on-screen keyboard allows you to enter characters, in particular letters, without an
external keyboard. To enter numbers and units, you can also use the DATA ENTRY
keys on the front panel of the instrument.
3.2.3.3 Step Size
A step symbol next to a numeric input field opens the "Step Size" dialog to define an
increment for data variation using the "Cursor Up/Down"
rotary knob.
buttons in the dialogs or the
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The input value for the step size takes effect immediately; see chapter 3.2.3.1, "Imme-
diate vs. Confirmed Settings", on page 64. "Auto" activates the default step size for the
current input parameter.
3.2.3.4 Paste Marker List
A pull-down list symbol next to a numeric input field opens a list of all current stimulus
and response marker values of the active trace. Any of the marker values can be
selected as a numeric entry. If the physical unit of the selected marker value is inconsistent (mismatch of stimulus and response values) then the numeric value is used
without the unit.
The response values in the paste marker list are not updated as the analyzer continues
measuring, so they may differ from the values in the marker info field.
To open the paste marker list you can also click on the input field and use the space
bar of your keyboard or the checkmark key in the NAVIGATION keypad at the front
panel of the analyzer.
3.2.3.5 Numeric Entry Bar
Single numeric values can be entered using the input field of the numeric entry bar.
The numeric entry bar appears just below the menu bar as soon as a function implying
a single numeric entry is activated. In contrast to dialogs, it does not hide any of the
display elements in the diagram area.
The numeric entry bar contains the name of the calling function, a numeric input field
including the "Cursor Up/Down" buttons for data variation and a step symbol
, and a
"Close" button. Besides it is closed automatically as soon as an active display element
in the diagram area is clicked or a new menu command is activated.
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3.2.4 Display Formats and Diagram Types
A display format defines how the set of (complex) measurement points is converted
and displayed in a diagram. The display formats in the "Trace – Format" menu use the
following basic diagram types:
●
Cartesian (rectangular) diagrams are used for all display formats involving a conversion of the measurement data into a real (scalar) quantity, i.e. for "dB Mag",
"Phase", "Delay", "SWR", "Lin Mag", "Real", "Imag" and "Unwrapped Phase".
●
Polar diagrams are used for the display format "Polar" and show a complex quantity as a vector in a single trace.
●
Smith charts are used for the display format "Smith". They show a complex quantity like polar diagrams but with grid lines of constant real and imaginary part of the
impedance.
●
Inverted Smith charts are used for the display format "Inverted Smith". They show
a complex quantity like polar diagrams but with grid lines of constant real and
imaginary part of the admittance.
The analyzer allows arbitrary combinations of display formats and measured quantities
("Trace – Measure"). Nevertheless, in order to extract useful information from the data,
it is important to select a display format which is appropriate to the analysis of a particular measured quantity; see chapter 3.2.4.6, "Measured Quantities and Display For-
mats", on page 75.
3.2.4.1 Cartesian Diagrams
Cartesian diagrams are rectangular diagrams used to display a scalar quantity as a
function of the stimulus variable (frequency / power / time).
●
The stimulus variable appears on the horizontal axis (x-axis), scaled linearly
(sweep types "Lin Frequency", "Power", "Time", "CW Mode") or logarithmically
(sweep type "Log Frequency").
●
The measured data (response values) appears on the vertical axis (y-axis). The
scale of the y-axis is linear with equidistant grid lines although the y-axis values
may be obtained from the measured data by non-linear conversions.
The following examples show the same trace in Cartesian diagrams with linear and
logarithmic x-axis scaling.
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3.2.4.2 Conversion of Complex into Real Quantities
The results in the "Trace – Measure" menu can be divided into two groups:
●
"S-Parameters", "Ratios", "Wave Quantities", "Impedances", "Admittances", "ZParameters", and "Y-Parameters" are complex.
●
"Stability Factors" and "DC Input" values (voltages, PAE) are real.
The following table shows how the response values in the different Cartesian diagrams
are calculated from the complex measurement values z = x + jy (where x, y, z are functions of the sweep variable). The formulas also hold for real results, which are treated
as complex values with zero imaginary part (y = 0).
Trace Format Description Formula
dB Mag Magnitude of z in dB |z| = sqrt ( x2 + y2 )
Lin Mag Magnitude of z, unconverted |z| = sqrt ( x2 + y2 )
Phase Phase of z φ (z) = arctan (y/x)
Real Real part of z Re(z) = x
Imag Imaginary part of z Im(z) = y
dB Mag(z) = 20 * log|z| dB
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Trace Format Description Formula
SWR (Voltage) Standing Wave Ratio SWR = (1 + |z|) / (1 – |z|)
Delay Group delay, neg. derivative of the
An extended range of formats and conversion formulas is available for markers. To
convert any point on a trace, create a marker and select the appropriate marker format.
Marker and trace formats can be selected independently.
3.2.4.3 Polar Diagrams
Polar diagrams show the measured data (response values) in the complex plane with a
horizontal real axis and a vertical imaginary axis. The grid lines correspond to points of
equal magnitude and phase.
●
The magnitude of the response values corresponds to their distance from the center. Values with the same magnitude are located on circles.
●
The phase of the response values is given by the angle from the positive horizontal
axis. Values with the same phase are on straight lines originating at the center.
The following example shows a polar diagram with a marker used to display a pair of
stimulus and response values.
– d φ (z) / dΩ (Ω = 2π * f)
phase response
Example: Reflection coefficients in polar diagrams
If the measured quantity is a complex reflection coefficient (S11, S22 etc.), then the center of the polar diagram corresponds to a perfect load Z0 at the input test port of the
DUT (no reflection, matched input), whereas the outer circumference (|Sii| = 1) represents a totally reflected signal.
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Examples for definite magnitudes and phase angles:
●
The magnitude of the reflection coefficient of an open circuit (Z = infinity, I = 0) is
one, its phase is zero.
●
The magnitude of the reflection coefficient of a short circuit (Z = 0, U = 0) is one, its
phase is –180 deg.
3.2.4.4 Smith Chart
The Smith chart is a circular diagram that maps the complex reflection coefficients S
to normalized impedance values. In contrast to the polar diagram, the scaling of the
diagram is not linear. The grid lines correspond to points of constant resistance and
reactance.
●
Points with the same resistance are located on circles.
●
Points with the same reactance produce arcs.
The following example shows a Smith chart with a marker used to display the stimulus
value, the complex impedance Z = R + j X and the equivalent inductance L.
ii
A comparison of the Smith chart, the inverted Smith chart and the polar diagram
reveals many similarities between the two representations. In fact the shape of a trace
does not change at all if the display format is switched from "Polar" to "Smith" or "Inverted Smith" – the analyzer simply replaces the underlying grid and the default marker
format.
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,
)Im()Re(1
)Im()Re(1
)/Re(
2
2
22
0
ZZR
2
2
0
)Im()Re(1
)Im(2
)/Im(
ZZX
System Overview
Screen Elements
Smith chart construction
In a Smith chart, the impedance plane is reshaped so that the area with positive resistance is mapped into a unit circle.
The basic properties of the Smith chart follow from this construction:
●
The central horizontal axis corresponds to zero reactance (real impedance). The
center of the diagram represents Z/Z0 = 1 which is the reference impedance of the
system (zero reflection). At the left and right intersection points between the horizontal axis and the outer circle, the impedance is zero (short) and infinity (open).
●
The outer circle corresponds to zero resistance (purely imaginary impedance).
Points outside the outer circle indicate an active component.
●
The upper and lower half of the diagram correspond to positive (inductive) and
negative (capacitive) reactive components of the impedance, respectively.
Example: Reflection coefficients in the Smith chart
If the measured quantity is a complex reflection coefficient Γ (e.g. S11, S22), then the
unit Smith chart can be used to read the normalized impedance of the DUT. The coor-
dinates in the normalized impedance plane and in the reflection coefficient plane are
related as follows (see also: definition of matched-circuit (converted) impedances):
Z / Z0 = (1 + Γ) / (1 – Γ)
From this equation it is easy to relate the real and imaginary components of the complex resistance to the real and imaginary parts of Γ:
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According to the two equations above, the graphical representation in a Smith chart
has the following properties:
●
Real reflection coefficients are mapped to real impedances (resistances).
●
The center of the Γ plane (Γ = 0) is mapped to the reference impedance Z0,
whereas the circle with |Γ| = 1 is mapped to the imaginary axis of the Z plane.
●
The circles for the points of equal resistance are centered on the real axis and
intersect at Z = infinity. The arcs for the points of equal reactance also belong to
circles intersecting at Z = infinity (open circuit point (1, 0)), centered on a straight
vertical line.
Examples for special points in the Smith chart:
●
The magnitude of the reflection coefficient of an open circuit (Z = infinity, I = 0) is
one, its phase is zero.
●
The magnitude of the reflection coefficient of a short circuit (Z = 0, U = 0) is one, its
phase is –180 deg.
3.2.4.5 Inverted Smith Chart
The inverted Smith chart is a circular diagram that maps the complex reflection coefficients S"ii" to normalized admittance values. In contrast to the polar diagram, the scaling of the diagram is not linear. The grid lines correspond to points of constant conductance and susceptance.
●
Points with the same conductance are located on circles.
●
Points with the same susceptance produce arcs.
The following example shows an inverted Smith chart with a marker used to display the
stimulus value, the complex admittance Y = G + j B and the equivalent inductance L.
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A comparison of the inverted Smith chart with the Smith chart and the polar diagram
reveals many similarities between the different representations. In fact the shape of a
trace does not change at all if the display format is switched from "Polar" to "Inverted
Smith" or "Smith" – the analyzer simply replaces the underlying grid and the default
marker format.
Inverted Smith chart construction
The inverted Smith chart is point-symmetric to the Smith chart:
The basic properties of the inverted Smith chart follow from this construction:
●
The central horizontal axis corresponds to zero susceptance (real admittance). The
center of the diagram represents Y/Y0 = 1, where Y0 is the reference admittance of
the system (zero reflection). At the left and right intersection points between the
horizontal axis and the outer circle, the admittance is infinity (short) and zero
(open).
●
The outer circle corresponds to zero conductance (purely imaginary admittance).
Points outside the outer circle indicate an active component.
●
The upper and lower half of the diagram correspond to negative (inductive) and
positive (capacitive) susceptive components of the admittance, respectively.
Example: Reflection coefficients in the inverted Smith chart
If the measured quantity is a complex reflection coefficient G (e.g. S11, S22), then the
unit inverted Smith chart can be used to read the normalized admittance of the DUT.
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2
2
22
0
)Im()Re(1
)Im()Re(1
)/Re(
YYG
,
)Im()Re(1
)Im(2
)/Im(
2
2
0
YYB
System Overview
Screen Elements
The coordinates in the normalized admittance plane and in the reflection coefficient
plane are related as follows (see also: definition of matched-circuit (converted) admittances):
Y / Y0 = (1 - Γ) / (1 + Γ)
From this equation it is easy to relate the real and imaginary components of the complex admittance to the real and imaginary parts of Γ:
According to the two equations above, the graphical representation in an inverted
Smith chart has the following properties:
●
Real reflection coefficients are mapped to real admittances (conductances).
●
The center of the Γ plane (Γ = 0) is mapped to the reference admittance Y0,
whereas the circle with |Γ| = 1 is mapped to the imaginary axis of the Y plane.
●
The circles for the points of equal conductance are centered on the real axis and
intersect at Y = infinity. The arcs for the points of equal susceptance also belong to
circles intersecting at Y = infinity (short circuit point (–1, 0)), centered on a straight
vertical line.
Examples for special points in the inverted Smith chart:
●
The magnitude of the reflection coefficient of a short circuit (Y = infinity, U = 0) is
one, its phase is –180 deg.
●
The magnitude of the reflection coefficient of an open circuit (Y = 0, I = 0) is one, its
phase is zero.
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Measured Quantities
3.2.4.6 Measured Quantities and Display Formats
The analyzer allows any combination of a display format and a measured quantity. The
following rules can help to avoid inappropriate formats and find the format that is ideally suited to the measurement task.
●
All formats are suitable for the analysis of reflection coefficients Sii. The formats
"SWR", "Smith" and "Inverted Smith" lose their original meaning (standing wave
ratio, normalized impedance or admittance) if they are used for transmission Sparameters, ratios and other quantities.
●
The complex "Impedances", "Admittances", "Z-parameters", and "Y-parameters"
are generally displayed in one of the Cartesian diagrams with linear vertical axis
scale or in a polar diagram.
●
The real "Stability Factors", "DC Inputs", and the "PAE" is generally displayed in a
linear Cartesian diagram ("Lin Mag" or "Real"). In complex formats, real numbers
represent complex numbers with zero imaginary part.
The following table gives an overview of recommended display formats.
Lin Mag ON ON (default for Z-parameters, Y-param-
Complex dimensionless quantities:
S-parameters and ratios
Complex quantities with dimensions:
Wave quantities, Z-parameters, Yparameters, impedances, admittances
eters, impedances, admittances)
Real quantities:
Stability Factors, DC Input
½, PAE
ON (default)
dB Mag ON (default) ON (default for wave quantities) –
Phase ON ON –
Real ON ON ON
Imag ON ON –
Unwrapped Phase ON ON –
Smith ON (reflection coefficients Sii) – –
Polar ON – –
Inverted Smith ON (reflection coefficients Sii) – –
SWR ON (reflection coefficients Sii) – –
Delay ON (transmission coefficients Sij) – –
The default formats are activated automatically when the measured quantity is
changed.
3.3 Measured Quantities
This section gives an overview of the measurement results of the network analyzer and
the meaning of the different measured quantities. All quantities can be selected in the
"Trace – Meas" submenu.
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2
1
2221
1211
2
1
a
a
SS
SS
b
b
System Overview
Measured Quantities
The definitions in this and the following sections apply to general n-port DUTs. An analyzer with a smaller number of test ports provides a subset of the n-port quantities.
3.3.1 S-Parameters
S-parameters are the basic measured quantities of a network analyzer. They describe
how the DUT modifies a signal that is transmitted or reflected in forward or reverse
direction. For a 2-port measurement the signal flow is as follows.
The figure above is sufficient for the definition of S-parameters but does not necessarily show the complete signal flow. In fact, if the source and load ports are not ideally
matched, part of the transmitted waves are reflected off the receiver ports so that an
additional a2 contribution occurs in forward measurements, an a1 contribution occurs in
reverse measurements. The 7-term calibration types Txx take these additional contributions into account.
The scattering matrix links the incident waves a1, a2 to the outgoing waves b1, b
according to the following linear equation:
2
Meaning of 2-port S-parameters
The four 2-port S-parameters can be interpreted as follows:
●
S11 is the input reflection coefficient, defined as the ratio of the wave quantities
b1/a1, measured at PORT 1 (forward measurement with matched output and a2 =
0).
●
S21 is the forward transmission coefficient, defined as the ratio of the wave quantities b2/a1 (forward measurement with matched output and a2 = 0).
●
S12 is the reverse transmission coefficient, defined as the ratio of the wave quantities b1 (reverse measurement with matched input, b
0) to a2.
●
S22 is the output reflection coefficient, defined as the ratio of the wave quantities b
(reverse measurement with matched input, b
a2, measured at PORT 2.
2,rev
in the figure above and a1 =
1,rev
in the figure above and a1 = 0) to
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a
a
a
a
SSSS
SSSS
SSSS
SSSS
b
b
b
b
4
3
2
1
44434241
34333231
24232221
14131211
4
3
2
1
System Overview
Measured Quantities
Meaning of squared amplitudes
The squared amplitudes of the incident and outgoing waves and of the matrix elements
have a simple meaning:
Table 3-1: Squared S-parameters
|a1|
2
Available incident power at the input of a two-port (= the power provided by a generator with a source impedance equal to the reference impedance Z0)
2
|a2|
2
|b1|
2
|b2|
10*log|S11|2 (= 20*log|S11|)
10*log|S22|
10*log|S21|
10*log|S12|
3.3.1.1 Multiport S-Parameters
2
2
2
The multiport S-parameters extend the standard 2-port S-parameters to a larger number of incoming and outgoing waves. For a 4-port DUT,
where ai denotes the incident and bi the outgoing wave at DUT port i = 1 to 4, and the
S-parameters are expressed as Sij (i,j = 1 to 4).
Available incident power at the output
Reflected power at the input of a two-port
Reflected power at the output
Reflection loss at the input
Reflection loss at the output
Insertion loss at the input
Insertion loss at the output
The parameters conisdered so far are referred to as single-ended S-parameters. The
S-parameter description can also be used to describe different propagation modes of
the waves at the output and input ports. This results in so-called mixed mode S-parameters. The analyzer measures either single-ended or mixed mode S-parameters.
3.3.2 Impedance Parameters
An impedance is the complex ratio between a voltage and a current. The analyzer provides two independent sets of impedance parameters:
●
Converted impedances (each impedance parameter is obtained from a single Sparameter)
●
Z-parameters (complete description of the n-port DUT)
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ii
ii
iii
S
S
ZZ
1
1
0
,,2
00
00
jiZZ
S
ZZ
Z
ji
ij
ji
ij
System Overview
Measured Quantities
3.3.2.1 Converted Impedances
The converted impedance parameters describe the input impedances of a DUT with
fully matched outputs. In the figures below the indices I and j number the analyzer/DUT
ports, Z0i is the reference impedance at the DUT port I.
The analyzer converts a single measured S-parameter to determine the corresponding
converted impedance. As a result, converted Z-parameters cannot completely describe
general n-port DUTs:
●
A reflection parameter Zii completely describes a one-port DUT. For n-port DUTs
(n>1) the reflection parameters Zii describe the input impedances at ports I (I = 1 to
n) under the condition that each of the other ports is terminated with its reference
impedance (matched-circuit parameters).
●
A two-port transmission parameter Zij (i ≠ j) can describe a pure serial impedance
between the two ports.
Relation with S-parameters
The converted impedances Zii are calculated from the reflection S-parameters S
according to:
The transmission parameters are calculated according to:
The converted admittances are defined as the inverse of the impedances.
Examples:
●
Z11 is the input impedance of a 2-port DUT that is terminated at its output with the
reference impedance Z0 (matched-circuit impedance measured in a forward reflection measurement).
●
The extension of the impedances to more ports and mixed mode measurements is
analogous to S-parameters. Z
is the differential mode input impedance at port 4
dd44
of a DUT that is terminated at its other ports with the reference impedance Z0.
ii
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IZIZV
IZIZV
System Overview
Measured Quantities
You can also read the converted impedances in a reflection coefficient measurement
from the Smith chart.
3.3.2.2 Z-Parameters
The Z-parameters describe the impedances of a DUT with open output ports (I = 0).
The analyzer provides the full set of Z-parameters including the transfer impedances
(i.e. the complete nxn Z-matrix for an n port DUT).
This means that Z-parameters can be used as an alternative to S-parameters (or Yparameters) in order to completely characterize a linear n-port network.
3.3.2.3 2-Port Z-Parameters
In analogy to S-parameters, Z-parameters are expressed as Zij, where i denotes the
measured and j the stimulated port.
The Z-parameters for a two-port are based on a circuit model that can be expressed
with two linear equations:
Meaning of Z-parameters
The four 2-port open-circuit Z-parameters can be interpreted as follows:
●
Z11 is the input impedance, defined as the ratio of the voltage V1 to the current I1,
measured at port 1 (forward measurement with open output, I2 = 0).
●
Z21 is the forward transfer impedance, defined as the ratio of the voltage V2 to the
current I1 (forward measurement with open output, I2 = 0).
●
Z12 is the reverse transfer impedance, defined as the ratio of the voltage V1 to the
current I2 (reverse measurement with open input, I1 = 0).
●
Z22 is the output impedance, defined as the ratio of the voltage V2 to the current I2,
measured at port 2 (reverse measurement with open input, I1 = 0).
Z-parameters can be easily extended to describe circuits with more than two ports or
several modes of propagation.
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ii
ii
ii
i
ii
Z
S
S
Z
Y /1
1
11
0
99...,,1,,,/1
2
0000
jijiZ
ZZSZZ
S
Y
ij
jiijji
ij
ij
System Overview
Measured Quantities
3.3.2.4 Admittance Parameters
An admittance is the complex ratio between a current and a voltage. The analyzer provides two independent sets of admittance parameters:
●
Converted admittances (each admittance parameter is obtained from a single Sparameter)
●
Y-parameters (complete description of the n-port DUT)
3.3.2.5 Converted Admittances
The converted admittance parameters describe the input admittances of a DUT with
fully matched outputs. The converted admittances are the inverse of the converted
impedances.
The analyzer converts a single measured S-parameter to determine the corresponding
converted admittance. As a result, converted Y-parameters cannot completely describe
general n-port DUTs:
●
A reflection parameter Yii completely describes a one-port DUT. For n-port DUTs
(n>1) the reflection parameters Yii describe the input admittances at ports I (I = 1 to
n) under the condition that each of the other ports is terminated with its reference
impedance (matched-circuit parameters).
●
A two-port transmission parameter Yij (I ≠ j) can describe a pure serial impedance
between the two ports.
Relation with S-parameters
The converted admittances Yii are calculated from the reflection S-parameters S
according to:
The transmission parameters are calculated according to:
Examples:
●
Y11 is the input admittance of a 2-port DUT that is terminated at its output with the
reference impedance Z0 (matched-circuit admittance measured in a forward reflection measurement).
●
The extension of the admittances to more ports and mixed mode measurements is
analogous to S-parameters. Y
is the differential mode input admittance at port 4
dd44
of a DUT that is terminated at its other ports with the reference impedance Z0.
ii
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VYVYI
VYVYI
System Overview
Measured Quantities
You can also read the converted admittances in a reflection coefficient measurement
from the inverted Smith chart.
3.3.2.6 Y-Parameters
The Y-parameters describe the admittances of a DUT with output ports terminated in a
short circuit (V = 0). The analyzer provides the full set of Y-parameters including the
transfer admittances (i.e. the complete n x n Y-matrix for an n port DUT).
This means that Y-parameters can be used as an alternative to S-parameters (or Zparameters) in order to completely characterize a linear n-port network.
3.3.2.7 2-Port Y-Parameters
In analogy to S-parameters, Y-parameters are expressed as Y
and <in> denote the output and input port numbers of the DUT. In analogy to Z-param-
eters, the Y-parameters for a two-port are based on a circuit model that can be
expressed with two linear equations:
Meaning of Y-parameters
The four 2-port Y-parameters can be interpreted as follows:
●
Y11 is the input admittance, defined as the ratio of the current I1 to the voltage V1,
measured at port 1 (forward measurement with output terminated in a short circuit,
V2 = 0).
●
Y21 is the forward transfer admittance, defined as the ratio of the current I2 to the
voltage V1 (forward measurement with output terminated in a short circuit, V2 = 0).
●
Y12 is the reverse transfer admittance, defined as the ratio of the current I1 to the
voltage V2 (reverse measurement with input terminated in a short circuit, V1 = 0).
●
Y22 is the output admittance, defined as the ratio of the current I2 to the voltage V2,
measured at port 2 (reverse measurement with input terminated in a short circuit,
V1 = 0).
<out>< in>
, where <out>
Y-parameters can be easily extended to describe circuits with more than two ports or
several modes of propagation.
3.3.2.8 Wave Quantities and Ratios
The elements of the S-, Z- and Y-matrices represent fixed ratios of complex wave
amplitudes. As long as the assumption of linearity holds, the S-, Z- and Y-parameters
are independent of the source power.
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Measured Quantities
The network analyzer provides two additional sets of measurement parameters which
have a unambiguous meaning even if the DUT is measured outside its linear range:
●
"Wave Quantities" provide the power of any of the transmitted or received waves.
●
"Ratios" provide the complex ratio of any combination of transmitted or received
wave quantities.
In contrast to S-, Z- and Y-parameters, wave quantities and ratios are not system-error
corrected. A power calibration can be applied to wave quantities and ratios.
With option R&S ZVA-K6, "True Differential Mode", the analyzer can also determine
balanced wave quantities and ratios.
3.3.2.9 Wave Quantities
A wave quantity measurement provides the power of any of the transmitted or received
waves. The power can be displayed in voltage units (e.g. "V" or "dBmV") or equivalent
power units (e.g. "W" or "dBm").
Examples for using wave quantities
The wave quantities provide the power at the different receive ports of the analyzer.
This is different from an S-parameter measurement, where the absolute power of a linear device is cancelled. Wave quantities are therefore suitable for the following measurement tasks:
●
Analysis of non-linearities of the DUT.
●
Use of the analyzer as a selective power meter.
To increase the accuracy or correct a possible attenuation in the input signal path,
it is recommended to perform a power calibration.
The notation for wave quantities includes the direction and the test port number. Additionally, the source port must be specified. The letter a indicates a transmitted wave, b
a received wave.
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Measured Quantities
Examples:
●
a1 Src Port 1 is the outgoing wave at test port 1. In a standard S-parameter measurement, this wave is fed to the input port (port 1) of the DUT (forward measure-
ment).
●
b1 Src Port 1 is the incoming wave at test port 1. In a standard S-parameter measurement, this is the reflected wave at port 1 of the DUT (forward measurement).
3.3.2.10 Ratios
A ratio measurement provides the complex ratio of any combination of transmitted or
received wave amplitudes. Ratios complement the S-parameter measurements, where
only ratios of the form bI/aj (ratio of the incoming wave to the outgoing wave at the test
ports I and j of the DUT) are considered.
Examples for using ratios
A measurement of ratios is particularly suitable for the following test scenarios:
●
The test setup or some of its components (e.g. active components or non-reciprocal devices) do not allow a system error correction so that a complete S-parameter
measurement is not possible.
●
The test setup contains frequency-converting components so that the transmitted
and the received waves are at different frequencies.
●
A ratio of two arbitrary waves that is not an element of the S-matrix (e.g. a ratio of
the form aI/aj) is needed.
The notation for ratios includes the two waves with their directions and test port numbers. Additionally, the source port must be specified. In analogy to wave quantities, the
letter a indicates an outgoing wave, b an incoming wave.
Examples:
●
b2/a1 Src Port 1 is the ratio of the outgoing wave b2 at port 2 and the incident wave
a1 at port 1; this corresponds to the S-parameter S21 (forward transmission coefficient).
●
b1/a1 Src Port 1 is the ratio of the wave quantities b1 and a1, measured at PORT 1;
this corresponds to the S-parameter S11 (input reflection coefficient).
3.3.2.11 Unbalance-Balance Conversion
Unbalance-balance conversion is the simulation of one or more unbalance-balance
transformers (baluns) integrated in the measurement circuit in order to convert the
DUT ports from an unbalanced state into a balanced state and virtually separate the
differential and common mode signals. The analyzer measures the unbalanced state
but converts the results and calculates mixed mode parameters, e.g. mixed mode Sparameters. No physical transformer is needed.
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Measured Quantities
With option R&S ZVA-K6, True Differential Mode, the analyzer can generate balanced
waves at arbitrary reference planes in the test setup and determine balanced results
such as S-parameters, wave quantities and ratios. The true differential mode also provides two additional sweep types, the "amplitude imbalance" and "phase imbalance"
sweeps. What is said below is valid for both the simulated balanced mode and the true
differential mode.
To perform balanced measurements, a pair of physical analyzer ports is combined to
form a logical port. The balanced port of the DUT is directly connected to the analyzer
ports
Unbalance-balance conversion avoids the disadvantages of real transformers:
●
There is no need to fabricate test fixtures with integrated baluns for each type of
DUT.
●
The measurement is not impaired by the non-ideal characteristics of the balun (e.g.
error tolerances, limited frequency range).
●
Calibration can be performed at the DUT's ports. If necessary (e.g. to compensate
for the effect of a test fixture), it is possible to shift the calibration plane using
length offset parameters.
●
Differential and common mode parameters can be evaluated with a single test
setup.
3.3.2.12 Balanced Port Configurations
Defining a logical ports requires two physical analyzer ports. The ports of an analyzer
are equivalent and can be freely combined. Moreover, it is possible to assign arbitrary,
independent reference impedance values to each unbalanced port and to the differential and common mode of each logical port. The following types of balanced devices
can be measured with 2-port, 3-port and 4-port analyzers:
2-port analyzers: Reflection measurements on 1 balanced port
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Measured Quantities
Balanced port:
Differential mode
DUT
Bal.
port
Log.
NWA
port
= Z
Z
0d
ref
Common mode
= Z
Z
0c
ref
3-port analyzers: Reflection and transmission measurements on 1 balanced port
Balanced port:
Differential mode
= Z
Z
0d
ref
Common mode
= Z
Z
0c
ref
Log.
NWA
port
Bal.
port
DUT
Bal.
port
NWA
Balanced port:
Differential mode
Log.
port
Common mode
= Z
Z
0d
ref
= Z
Z
0c
ref
4-port analyzers: Reflection and transmission measurements on 1 or 2 balanced ports
Single-ended
(unbalanced) ports
= Z
Z
connector1
ref1
= Z
Z
connector2
ref2
Balanced port:
Differential mode
= Z
Z
0d
ref
Common mode
= Z
Z
0c
ref
Log.
NWA
port
Single
ended
ports
Bal.
port
Bal.
port
DUT
Bal.
port
DUT
Balanced port:
Differential mode
Log.
NWA
port
Differential mode
Log.
NWA
port
= Z
Z
0d
ref
Common mode
= Z
Z
0c
ref
Balanced port:
= Z
Z
0d
ref
Common mode
= Z
Z
0c
ref
A balanced port configuration is defined by simply selecting the pairs of physical ports
that are combined to form balanced ports and defining the two reference impedances
for the differential and common mode at each balanced port. All this is done in a single
dialog; refer to the help system for details and measurement examples. The most commonly used balanced port configurations and impedances are predefined and can be
selected in the "Measurement Wizard".
Depending on the test setup, the analyzer provides different types of mixed mode
parameters; refer to the following sections for details.
3.3.2.13 Mixed Mode Parameters
Mixed mode parameters are an extension of normal mode parameters (e.g. S-parameters, impedances and admittances) for balanced measurements. The analyzer can
measure mixed mode parameters as soon as a balanced port configuration is selected.
Mixed mode parameters are used to distinguish the following three port modes:
●
s: Single-ended (for unbalanced ports)
●
d: Differential mode (for balanced ports)
●
c: Common mode (for balanced ports)
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Measured Quantities
The notation of a general S-parameter is S
<mout><min><out><in>
, where <mout> and <min>
denote the output and input port modes, <out> and <in> denote the output and input
port numbers.
Meaning of 2-port mixed mode S-parameters
The mixed mode 2-port S-parameters can be interpreted as follows:
●
S
<mout><min>11
is the mixed mode input reflection coefficient, defined as the ratio of
the wave quantities b1 (mode mout) to a1 (mode min), measured at PORT 1 (forward measurement with matched output and a2 = 0).
●
S
<mout><min>21
is the mixed mode forward transmission coefficient, defined as the
ratio of the wave quantities b2 (mode mout) to a1 (mode min) (forward measurement with matched output and a2 = 0).
●
S
<mout><min>12
is the mixed mode reverse transmission coefficient, defined as the
ratio of the wave quantities b1 (mode mout) (reverse measurement with matched
input, b1' in the figure above and a1 = 0) to a2 (mode min).
●
S
<mout><min>22
is the mixed mode output reflection coefficient, defined as the ratio of
the wave quantities b2 (mode mout) (reverse measurement with matched input, b2'
in the figure above and a1 = 0) to a2 (mode min), measured at PORT 2.
If <mout> is different from <min>, the S-parameters are called mode conversion factors.
3.3.2.14 Mixed Mode Parameters for Different Test Setups
Which types of mixed mode parameter are available depends on the measured device
and the port configuration of the analyzer. The following examples of mixed more
parameters can all be obtained with a 4-port analyzer.
1. DUT with only single-ended ports: No balanced port definition necessary, the analyzer provides single-ended multiport parameters.
2. DUT with one balanced port: Only reflection and mode conversion measurements
with differential and common mode parameters.
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Calibration
3. 3. DUT with one balanced and one single-ended port.
4. 4. DUT with two balanced ports or one balanced and two single-ended ports. Both
device types are fully characterized by 4x4 mixed mode S-matrices.
3.4 Calibration
Calibration or "system error correction" is the process of eliminating systematic, reproducible errors from the measurement results. The process involves the following
stages:
1. A set of calibration standards is selected and measured over the required sweep
range. For many calibration types the magnitude and phase response of each calibration standard (i.e. its S-parameters if no system errors occur) must be known
within the entire sweep range. In some calibration procedures (TRL, TNA, TRM),
part of the characteristics of the standards can be auto-determined due to implicit
redundancy (self-calibration).
2. The analyzer compares the measurement data of the standards with their known,
ideal response. The difference is used to calculate the system errors using a particular error model (calibration type) and derive a set of system error correction data.
3. The system error correction data is used to correct the measurement results of a
DUT that is measured instead of the standards.
Calibration is always channel-specific because it depends on the hardware settings, in
particular on the sweep range. The means that a system error correction data set is
stored with the calibrated channel.
The analyzer provides a wide range of sophisticated calibration methods for all types of
measurements. Which calibration method is selected depends on the expected system
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Calibration
errors, the accuracy requirements of the measurement, on the test setup and on the
types of calibration standards available.
Due to the analyzer's calibration wizard, calibration is a straightforward, menu-guided
process. Moreover, it is possible to perform the entire calibration process automatically
using a Calibration Unit (accessories R&S ZV-Z5x).
The system error correction data determined in a calibration procedure are stored on
the analyzer. You can read these correction data using the remote control command
[SENSe<Ch>:]CORRection:CDATa. You can also replace the correction data of the
analyzer by your own correction data sets.
A red label "Cal Off !" appears behind the trace list if the system error correction no
longer applies to one or more traces:
This may happen for one of the following reasons:
●
The sweep range is outside the calibrated frequency range.
●
The channel calibration is not sufficient for the measured quantity (e.g. a one-port
calibration has been performed, but the measured quantity is a transmission
parameter).
●
The system error correction has been switched off deliberately ("Correction Off").
●
The analyzer provides other labels to indicate the status of the current calibration;
refer to the Help system for details.
3.4.1 Calibration Standards and Calibration Kits
A calibration kit is a set of physical calibration standards for a particular connector type.
The magnitude and phase response of the calibration standards (i.e. their S-parameters) must be known or predictable within a given frequency range.
The standards are grouped into several types (Open, Through, Match,...) corresponding to the different input quantities for the analyzer's error models. The standard type
also determines the equivalent circuit model used to describe its properties. The circuit
model depends on several parameters that are stored in the cal kit file associated with
the calibration kit.
As an alternative to using circuit models, it is possible to describe the standards by
means of S-parameter tables stored in a file.
The analyzer provides a large number of predefined cal kits but can also import cal kit
files and create new kits:
●
A selection of predefined kits is available for all connector types. The parameters of
these kits are displayed in the "Add/Modify Standards" dialog, however, it is not
possible to change or delete the kits.
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System Overview
Calibration
●
Imported and user-defined kits can be changed in the "Calibration Kits" dialog and
its various sub-dialogs.
Calibration kits and connector types are global resources; the parameters are stored
independently and are available irrespective of the current setup.
3.4.2 Calibration Types
The analyzer provides a wide range of calibration types for one, two or more ports. The
calibration types differ in the number and types of standards used, the error terms, i.e.
the type of systematic errors corrected and the general accuracy. The following table
gives an overview.
Table 3-2: Overview of calibration types
Calibration Type Standards Parameters Error Terms General Accuracy Application
Reflection Normalization
Transmission Normalization
Full One-Port Open, Short and
One-Path Two-Port Open, Short and
Open or Short S
Through S12, S
1)
Match
Match1) (at source
port),
2)
Through
11
(or S22, ...)
(or S13,...)
S
11
(or S22, ...)
S11, S
(or S22,...)
Reflection tracking Low to medium Reflection measure-
ments on any port.
21
21
Transmission tracking
Reflection tracking,
Source match
Directivity,
Reflection tracking,
Source match,
Directivity,
Transmission tracking
Medium Transmission mea-
surements in any
direction and
between any combination of ports.
High Reflection measure-
ments on any port.
Medium to high Unidirectional trans-
mission measurements in any direction and between
any combination of
ports.
TOSM (2 or more
ports) or UOSM
TOM (2 or more
ports)
Open, Short,
Match1) at all ports,
Through2) between
all directed port
pairs
Open and Match at
all ports,
Through between
all directed port
pairs
All Reflection tracking,
Source match,
Directivity,
Load match,
Transmission tracking,
All Reflection tracking,
Source match,
Directivity,
Load match,
Transmission tracking
High Reflection and
transmission measurements on DUTs
with 2 or more
ports; classical 12term error correction model.
High, implicit verification
Reflection and
transmission measurements on DUTs
with 2 or more
ports.
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Calibration
Calibration Type Standards Parameters Error Terms General Accuracy Application
TRM (2 or more
ports)
TRL (2 or more
ports)
NIST Multiline TRL
(2 or more ports)
TNA (2 or more
ports)
Reflect (equal at all
ports) and Match at
all ports,
Through between
all directed port
pairs
Reflect at all ports,
Through and Line 1
[+ Line 2, Line 3
(optional)] between
all directed port
pairs, in combination with TRM
(optional)
Reflect at all ports,
Through and one or
more Line standards (number not
limited) between all
directed port pairs
Through, Attenuation, Symmetric
network
All Reflection tracking,
Source match,
Directivity,
Load match,
Transmission tracking
All Reflection tracking,
Source match,
Directivity,
Load match,
Transmission tracking
All Reflection tracking,
Source match,
Directivity, Load
match, Transmission tracking
All Reflection tracking,
Source match,
Directivity,
Load match,
Transmission tracking
High Reflection and
transmission measurements on DUTs
with 2 or ports,
especially in test fixtures.
High, high directivity
High, high directivity In general higher
accuracy than TRL
High, lowest
requirements on
standards
Reflection and
transmission measurements on DUTs
with 2 or more
ports, especially for
planar circuits. Limited bandwidth.
Reflection and
transmission measurements on DUTs
with 2 or more
ports, especially for
planar circuits.
Bandwidth limited at
low frequencies.
Reflection and
transmission measurements on DUTs
with 2 or more
ports, especially for
planar circuits.
1) Or any other 3 known one-port standards. To be used in a guided calibration, the
known standards must be declared to be open, short, and match irrespective of their
properties.
2) Or any other known two-port standard. See remark above.
The calibration type must be selected in accordance with the test setup. Select the calibration type for which you can obtain or design the most accurate standards and for
which you can measure the required parameters with best accuracy.
3.4.3 Automatic Calibration
A Calibration Unit is an integrated solution for automatic system error correction of vector network analyzers. For analyzers of the R&S ZVAB family, Rohde & Schwarz provides different types of calibration units:
●
The 2- and 4-port calibration units R&S ZV-Z51, R&S ZV-Z52, R&S ZV-Z53, R&S
ZV-Z54, and R&S ZV-Z55 are especially suited for R&S ZVA and R&S ZVB vector
network analyzers.
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Calibration
●
Within their respective frequency ranges, you may also use one of the calibration
units R&S ZN-Z51 (2 or 4 ports) or R&S ZN-Z151 (2 ports)
Calibration unit Recommended for Frequency range Connector type No. of ports Order no.
R&S ZV-Z51 R&S ZVB4, R&S
ZVB8, R&S ZVA8
R&S ZV-Z51 R&S ZVB4, R&S
ZVB8, R&S ZVA8
R&S ZV-Z52 R&S ZVB14, R&S
ZVB20, R&S
ZVA24
R&S ZV-Z52 R&S ZVB14 100 kHz to 18 GHz type N (f) 4 1164.0521.70
R&S ZV-Z53 R&S ZVB14, R&S
ZVB20, R&S
ZVA24
R&S ZV-Z53 R&S ZVB14 300 kHz to 18 GHz type N (f) 2 1164.0473.72
R&S ZV-Z54 R&S ZVA40 10 MHz to 40 GHz 2.92 mm (f) 2 1164.0467.92
R&S ZV-Z55 R&S ZVA50 10 MHz to 50 GHz 2.4 mm (f) 2 1164.0480.42
R&S ZN-Z51 R&S ZVB4, R&S
ZVB8
R&S ZN-Z51 R&S ZVB4, R&S
ZVB8
R&S ZN-Z51 R&S ZVB4, R&S
ZVB8
300 kHz to 8 GHz 3.5 mm (f) 4 1164.0515.30
300 kHz to 8 GHz type N (f) 4 1164.0515.70
10 MHz to 24 GHz 3.5 mm (f) 4 1164.0521.30
300 kHz to 24 GHz 3.5 mm (f) 2 1164.0473.32
100 kHz to 8.5 GHz 3.5 mm (f) 4 1319.5507.34
100 kHz to 8.5 GHz 3.5 mm (f) 2 1319.5507.32
100 kHz to 8.5 GHz type N (f) 4 1319.5507.74
R&S ZN-Z51 R&S ZVB4, R&S
ZVB8
100 kHz to 8.5 GHz type N (f) 2 1319.5507.72
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Calibration
Calibration unit Recommended for Frequency range Connector type No. of ports Order no.
R&S ZN-Z51
custom configuration
R&S ZN-Z151 R&S ZVB4, R&S
R&S ZN-Z151 R&S ZVB4, R&S
R&S ZN-Z153 R&S ZVB4, R&S
R&S ZVB4, R&S
ZVB8
ZVB8
ZVB8
ZVB8
The multiport calibration units R&S ZV-Z58, R&S ZV-Z59, R&S ZN-Z152 and R&S ZNZ154 are especially suited for R&S ZVT vector network analyzers.
The R&S ZN-Z51 allows a free/mixed port configuration with possible connector types
N (m/f), 3.5 mm (m/f) and 7/16 (m/f).
With an N(f)-type CalU serving as base unit, for each available port an alternative connector type N(m), 3.5 mm (m/f) or 7/16 (m/f) can be selected. For N(f)-type models
alternative connectors can be also be retrofitted, but the calibration unit has to be sent
to service for that and has to be characterized again. See the data sheet for ordering
information.
The frequency range for 7/16 connector ports is limited to 100 kHz to 7.5 GHz.
100 kHz to 8.5 GHz type N (f) 2 1317.9134.72
100 kHz to 8.5 GHz SMA (f) 2 1317.9134.32
100 kHz to 8.5 GHz SMA (f) 4 1319.6178.34
Calibration unit Recommended for Frequency range Connector type No. of ports Order no.
R&S ZV-Z58 R&S ZVT8 300 kHz to 8 GHz type N 8 1164.0638.78
R&S ZV-Z58 R&S ZVT8 300 kHz to 8 GHz 3.5 mm 8 1164.0638.78
R&S ZV-Z59 R&S ZVT20 10 MHz to 20 GHz 3.5 mm 6 1164.0450.36
R&S ZN-Z152 R&S ZVT8 100 kHz to 8.5 GHz SMA (f) 6 1319.6003.36
R&S ZN-Z153 R&S ZVT8 100 kHz to 8.5 GHz SMA (f) 4 1319.6178.34
The units contain calibration standards that are electronically switched when a calibration is performed. The calibration kit data for the internal standards are also stored in
the calibration unit, so that the analyzer can calculate the error terms and apply the calibration without any further input.
Advantages of automatic calibration
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Calibration
Automatic calibration is generally faster and more secure than manual calibration,
because:
●
There is no need to connect several standards manually. The number of connections to be performed quickly increases with the number of ports; see "TOSM Calibration".
●
Invalid calibrations due to operator errors (e.g. wrong standards or improper connections) are almost excluded.
●
No need to handle calibration kit data.
●
The internal standards don't wear out because they are switched electronically.
Automatic calibration is less flexible than manual calibration:
●
Some calibration types (TOM, TRM, TRL, TNA) are not available.
●
Automatic calibration cannot be performed for segmented frequency sweeps.
Please observe the safety instructions in the "Technical Information" provided with the
calibration unit to avoid any damage to the unit and the network analyzer. Safety-related aspects of the connection and operation of the units are also reported in the sections below.
3.4.4 Power Calibration
The purpose of a power calibration is to ensure accurate source power levels and
power readings at a particular position (reference plane) in the test setup. Power calibration is essentially different from the system error correction described in the previous sections. For best accuracy, a power calibration should be performed in addition to
a system error correction.
In general, a power calibration involves two stages:
1. Source power calibration: An external power meter is connected to the reference
plane. The analyzer modifies its source power until the power meter reading corresponds to the desired source power value.
2. Receiver power calibration: The analyzer uses the calibrated source signal to
adjust the power reading at the receiver port.
The analyzer provides power calibration wizards for various measurement modes.
3.4.5 Offset Parameters
Offset parameters complement the system error correction and power calibration, compensating for the known length and loss of a (non-dispersive and perfectly matched)
transmission line between the calibrated reference plane and the DUT. The analyzer
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can also auto-determine length and loss parameters, assuming that the actual values
should minimize the group delay and loss across the sweep range.
3.5 Optional R&S ZVA Extensions
The network analyzer can be upgraded with a number of hardware and software
options, providing enhanced flexibility and an extended measurement functionality. The
available options are listed in the "Info – Option Info" dialog. The R&S ZVA options listed below are described in detail in the reference chapters of the help system. For a
complete list of options, accessories, and extras refer to the product brochure of your
analyzer.
Table 3-3: R&S ZVA options
Option Option Name Functionality
RS& ZVAB-K2 Time Domain Transformation of the trace to time domain in order to analyze
responses, transformation back to the frequency domain.
R&S ZVA-K4 Arbitrary gen. and rec. frequen-
cies, includes scalar Mixer and
Harmonics measurements
R&S ZVA-K5 Mixer Phase Measurement (Vector
Mixer Measurement)
R&S ZVA-K6 True Differential Mode Generation of true differential and common mode stimuli at arbi-
Measurements at arbitrary (not necessarily equal) generator
and receiver frequencies; scalar measurements on external RF
mixers, harmonic distortion measurements, intermodulation distortion measurements.
Measurement of the parameters of an external mixer including
phase, e.g. the complex conversion loss or reflection coefficients.
trary reference planes in the test setup and measurement of the
mixed-mode S-parameters, wave quantities and ratios. Alternatively: Defined coherence mode, provides several source signals with defined phase and amplitude relation.
R&S ZVA-K7 Measurements on Pulsed Signals Pulsed measurements in analogy to a time sweep (i.e. at con-
stant receiver frequency), but with a much higher sampling rate
of 12.5/ns.
R&S ZVA-K8 Converter Control Measurements at frequencies beyond the analyzer's operating
range.
R&S ZVA-K9 Mixer Delay w/o LO Access Measurement of the absolute or relative group delay of a mixer.
R&S ZVA-K10 Long Distance Mixer Delay Mixer delay measurement with two different network analyzers,
one providing the source ports, the other the receive port.
R&S ZVA-K17 5 MHz Receiver Bandwidth Provides up to 5 MHz IF bandwidth, thus providing shorter mea-
surement times for frequency, time, or CW sweeps; enhanced
performance for point-in-pulse measurements.
R&S ZVA-K27 Internal Pulse Generators Provides two pulsed control signals to control pulsed measure-
ments.
R&S ZVAB-K30 Noise Figure Measurement Provides the noise figure of a DUT which operates in its linear
range.
R&S ZVA-K31 Freq. Conv. Noise Figure Provides the noise figure of a frequency-converting DUT which
operates in its linear range.
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Option Option Name Functionality
R&S ZVAB-B4 Oven Quartz (OCXO) The R&S ZVA can optionally be equipped with a 10 MHz oven-
controlled crystal oscillator (OCXO) to enhance the frequency
accuracy of the internal generators.
R&S ZVAB-B14 Universal Interface Provides digital control signals for an external part handler.
R&S ZVA<frequency>-B16 Direct Generator/Receiver Access Give direct access to various RF input and output signals, e.g.
to insert external components into the signal path or develop
custom measurements.
R&S ZVA<frequency>-B2x Generator Step Attenuators for
port x = 1,2,3,4
R&S ZVA<frequency>-B3x Receiver Step Attenuators for port
x = 1,2,3,4
The following sections provide a short introduction to the software options.
3.5.1 Time Domain (R&S ZVAB-K2)
The network analyzer measures and displays complex S-parameters and other quantities as a function of the frequency. The measurement results can be filtered and mathematically transformed in order to obtain the time domain representation, which often
gives a clearer insight into the characteristics of the DUT.
Time domain transforms can be calculated in band pass or low pass mode. For the latter the analyzer offers the impulse and step response as two alternative transformation
types. A wide selection of windows can be used to optimize the time domain response
and suppress sidelobes due to the finite sweep range. Moreover, it is possible to eliminate unwanted responses by means of a time gate and transform the gated result back
into the frequency domain.
3.5.2 Arbitrary Generator and Receiver Frequencies (R&S ZVA-K4)
Control the source power, e.g. to protect sensitive DUTs from
excess input levels.
Control the received power, e.g. to avoid damage to the analyzer.
Measurements at arbitrary (not necessarily equal) generator and receiver frequencies
provide a wealth of applications, e.g. intermodulation measurements vs. frequency and
power, hot S-parameter measurements.
For intermodulation distortion measurements, the analyzer provides a measurement
and calibration wizard. Intermodulation products and intercept points of order 3, 5, 7, 9
can be measured at the input and at the output of the DUT.
The frequency conversion option also includes mixer and harmonics measurements.
3.5.3 Arbitrary Gen. and Rec. Frequencies (R&S ZVA-K4)
RF mixers convert an RF signal at one frequency into a signal at another frequency.
The frequency that is to be shifted is applied at the RF input and the frequency shifting
signal (from a local oscillator, LO) is applied to the RF mixer's LO port, resulting in an
output signal at the mixer's Intermediate Frequency (IF) port.
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For a given RF signal, an ideal mixer would produce only two IF outputs: one at the
frequency sum of the RF and LO (IF = RF + LO), and another at the frequency difference between the RF and LO (IF = |RF – LO|). Filtering can be used to select one of
these IF outputs and reject the unwanted one.
In the scalar mixer mode the analyzer provides the following functionality:
●
Configuration of the RF and LO signals and measurement of the generated IF signal.
●
Power calibration of the signal sources and of the IF receiver.
●
The mixer mode can be used also to test important performance parameters of RF
mixers such as frequency ranges, conversion loss, compression, and isolation.
Harmonics are signals at an integer multiple of the fundamental frequency. The fundamental is the first harmonic, the nth harmonic is n times the frequency of the fundamental. The production of harmonic frequencies by an electronic system when a signal
is applied at the input is known as harmonic distortion.
The purpose of the harmonics measurement is to measure the harmonic distortion of a
DUT. To this end the source remains at the fundamental frequency whereas the
receiver is set to n times the fundamental frequency. Two different types of results are
provided:
●
In the direct measurement, the nth harmonic of the stimulus signal is measured.
●
In the relative measurement, the nth harmonic of the stimulus signal is divided by
1st harmonic (fundamental) received from the DUT. The result corresponds to the
nth harmonic distortion factor.
3.5.4 Mixer Phase Measurement (R&S ZVA-K5)
Measurement of the parameters of an external mixer including phase, e.g. the complex
conversion loss or reflection coefficients. In contrast to scalar mixer measurements
(with option R&S ZVA-K4), mixer phase (or vector mixer) measurements provide magnitude and phase information, including group delay, about the mixer under test (MUT).
To assess the phase information, the IF signal at the mixer output is converted back to
the original RF frequency using a second MEAS mixer. A third REF mixer ensures that
the reference wave is converted back to the RF frequency.
3.5.5 True Differential Mode (R&S ZVA-K6)
Differential transmission lines and circuits are widely used, because their characteristics give them a lower susceptibility to electromagnetic interference. Linear balanced
devices can be tested with sufficient accuracy using the virtual differential mode, where
the vector network analyzer generates unbalanced stimulus signals and uses a mathematical transformation to convert unbalanced wave quantities into balanced S-parameters. A different behavior is expected for nonlinear balanced devices, where the transmission characteristics of the DUT may depend on how closely the stimulus signal
matches real operating conditions.
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In "True Differential Mode", the vector network analyzer generates true differential and
common mode stimuli at arbitrary reference planes in the test setup and determines
mixed-mode S-parameters, wave quantities and ratios. The true differential mode also
provides two additional sweep types, the amplitude imbalance and phase imbalance
sweeps.
As an alternative to true differential mode, the Defined Coherence Mode provides several source signals with defined phase and amplitude relation.
3.5.6 Measurements on Pulsed Signals (R&S ZVA-K7)
Measurements on pulsed RF signals are required in many areas of RF and microwave
technology. Pulsed signals are used in mobile phone applications and radar systems,
and amplifiers are typically designed for pulsed rather than continuous wave (CW) conditions.
The analyzer performs pulsed measurements in analogy to a time sweep (i.e. at constant receiver frequency), but with a much higher sampling rate of 12.5/ns. The raw I/Q
amplitudes are written into a ring buffer and processed at the end of each sweep. The
buffer size allows for a maximum recording time (sweep time) of 3 ms. Due to the high
sampling rate and the large IF bandwidths available, it is possible to obtain profiles for
pulse widths from approx. 200 ns to the maximum recording time. Of course it is also
possible to measure a sequence of pulses up to the maximum recording time.
3.5.7 Converter Control (R&S ZVA-K8)
Measurements at frequencies beyond the analyzer's operating range (mm-wave measurements) are achieved by combining a frequency-converting measurement with an
external test set (frequency converter). The frequency converters use frequency multipliers to transform the RF source signal from one of the network analyzer ports into a
high-frequency stimulus signal. A dual directional coupler separates the reference and
measurement channels from the waveguide test port. A second signal (Local Oscillator, LO) is used for down-conversion of the reference and measurement channels. The
LO signal can be provided either by a second analyzer port or by an external generator. The down-converted signals are fed to the REF IN and MEAS IN input connectors
of the analyzer port providing the RF source signal.
Option R&S ZVA-K8 also comprises option ZVA-K4, Frequency Conversion.
3.5.8 Mixer Delay w/o LO Access (R&S ZVA-K9)
Measurement of a mixer's absolute or relative group delay. The mixer delay measurement is an extension of the scalar mixer measurement: The network analyzer generates a two-tone RF signal as a mixer input signal and measures the converted IF signal at the mixer output. The mixer delay is derived from the relative phases of the twotone signals at the mixer input and the mixer output.
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Compared to conventional measurement methods, the mixer delay measurement
offers several additional advantages.
●
No external mixers are needed.
●
A network analyzer with standard functionality is sufficient.
●
Easy calibration using a calibration mixer.
3.5.9 Long Distance Mixer Delay (R&S ZVA-K10)
The mixer delay measurement can be performed with two different R&S ZVA or R&S
ZVT network analyzers, one providing the source ports, the other the receive port. The
two instruments can communicate with each other via LAN using LXI event messages.
This can be advantageous e.g. for measurements on DUTs with large dimensions
where the connection to a single instrument would require very long RF cables.
3.5.10 Internal Pulse Generators (R&S ZVA-K27)
Provides two independent control signals at the CASCADE output connector on the
rear panel of the network analyzer. The signals can be used to control an R&S ZVAXxx
Extension Unit equipped with a pulse modulator option.
3.5.11 Noise Figure Measurement (R&S ZVAB-K30)
Provides the noise figure of a DUT which operates in its linear range. The noise figure
of a device is the ratio of the output signal-to-noise ratio (SNR) to the input SNR, provided that a thermal noise signal is fed to the input. It is a measure of the degradation of
the SNR caused by the device.
The method of measurement offers several advantages:
●
No additional noise source is required.
●
The result can be obtained in a single sweep.
●
The test setup is as simple as for a basic transmission measurement: The DUT
must be connected only once. Moreover, it is possible to perform S-parameter
measurements in parallel to the noise figure measurement.
3.5.12 Frequency Converting Noise Figure Measurement (R&S ZVA-K31)
Provides the noise figure of a frequency-converting DUT, e.g. a mixer or a system of
two mixer stages. The measurement is performed in analogy to noise figure measurements on non-frequency-converting DUTs.
Mixer noise figure measurements also require options R&S ZVAB-K30 and R&S ZVAK4.
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Glossary: Frequently Used Terms
Glossary: Frequently Used Terms
A
Active channel: Channel belonging to the active trace. The active channel is highligh-
ted in the channel list below the diagram. The active channel is not relevant in remote
control where each channel can contain an active trace.
Active marker: Marker that can be changed using the settings of the Marker menu
(Delta Mode, Ref. Mkr -> Mkr, Mkr Format). The active marker is also used for the
Marker Functions. It appears in the diagram with an enlarged marker symbol and font
size and with a dot placed in front of the marker line in the info field.
Active menu: The menu containing the last executed command. If the softkey bar is
displayed (Display - Config./View - Softkey Labels on), then the active menu is indicated on top of the softkey bar.
Active trace (manual control): Trace that is selected to apply the settings in the
Trace menu. The active trace is highlighted in the trace list of the active diagram area.
It can be different from the active trace in remote control.
Active trace (remote control): One trace of each channel that has been selected as
the active trace (CALCulate<Ch>:PARameter:SELect <trace name>). Many
commands (e.g. TRACE...) act on the active trace. It can be different from the active
trace in manual control.
C
Cal pool: The cal pool is a collection of correction data sets (cal groups) that the ana-
lyzer stores in a common directory. Cal groups in the pool can beapplied to different
channels and setups.
Calibration: The process of removing systematic errors from the measurement (system error correction). See also TOSM, TOM, TRM, TRL, TNA...
Calibration kit: Set of physical calibration standards for a particular connector family.
Calibration standard: Physical device that has a known or predictable magnitude and
phase response within a given frequency range. Calibration standards are grouped into
several types (open, through, match,...) corresponding to the different input quantities
for the analyzer's error models.
Calibration unit: Integrated solution for automatic calibration of 1 to 4 ports (accessory R&S ZV-Zxx). The unit contains calibration standards that are electronically
switched when a calibration is performed.
Channel: A channel contains hardware-related settings to specify how the network
analyzer collects data. Each channel is stored in an independent data set. The channel
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Glossary: Frequently Used Terms
settings complement the definitions of the Trace menu; they apply to all traces
assigned to the channel.
Compression point: The x-dB compression point of an S-parameter or ratio is the
stimulus signal level where the magnitude of the measured quantity has dropped by x
dB compared to its value at small stimulus signal levels (small-signal value).
Confirmation dialog box: Standard dialog box that pops up to display an error message or a warning. The current action can be either continued (OK) or cancelled (Cancel) on closing the dialog box.
Crosstalk: The occurrence of a signal at the receive port of the analyzer which did not
travel through the test setup and the DUT but leaks through other internal paths.
Crosstalk causes an isolation error in the measurement which can be corrected by
means of a calibration.
CW frequency: Continuous Wave frequency; fixed stimulus frequency used in Power,
CW Time and CW Mode sweeps.
D
Data trace: Trace filled with measurement data and updated after each sweep
(dynamic trace).
Diagram area: Rectangular portion of the screen used to display traces. Diagram
areas are arranged in windows; they are independent of trace and channel settings.
Directivity error: Measurement error caused by a coupler or bridge in the analyzer's
source port causing part of the generated signal to leak through the forward path into
the receive path instead of being transmitted towards the DUT. The directivity error can
be corrected by means of a full one port calibration or one of the two-port calibration
methods (except normalization).
Discrete marker: The stimulus value of a discrete marker always coincides with a
sweep point so that the marker does not show interpolated measurement values.
E
Excursion: Difference between the response values at a local maximum (minimum) of
the trace and at the two closest local minima (maxima) to the left and to the right.
F
Forward: A measurement on a two-port DUT is said to be in forward direction if the
source signal (stimulus) is applied to port 1 of the DUT.
H
Harmonic: Integer multiple of the fundamental frequency. The fundamental is the first
harmonic, the nth harmonic is n times the frequency of the fundamental.
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