User’s Guide
Agilent Technologies 86030A Lightwave Component Analyzer System
© Copyright Agilent Technologies, Inc. 2000
All Rights Reserved. Reproduction, adaptation, or translation without prior written
permission is prohibited,
except as allowed under copyright laws.
Agilent Technologies Part No.
86030-90001
Printed in USA
April 2000
Agilent Technologies, Inc.
Lightwave Division
1400 Fountaingrove Parkway
Santa Rosa, CA 95403-1799,
USA
(707) 577-1400
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used to mark the positions of the instrument
power line switch.
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positions of the instrument power line
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ii
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iii
General Safety Considerations
General Safety Considerations
This product has been designed and tested in accordance with IEC Publication 1010, Safety Requirements for Electronic Measuring Apparatus, and has
been supplied in a safe condition. The instruction documentation contains
information and warnings which must be followed by the user to ensure safe
operation and to maintain the product in a safe condition.
WARNING If this product is not used as specified, the protection provided by the
equipment could be impaired. This product must be used in a normal
condition (in which all means for protection are intact) only.
WARNING No operator serviceable parts inside. Refer servicing to qualified
personnel. To prevent electrical shock, do not remove covers.
iv
Contents
General Safety Considerations iv
1 Getting Started
Configuration Options 1-6
Front Panel Features 1-8
Rear Panel Features 1-11
Software Overview 1-12
File Menu 1-13
Options Menu 1-20
Tools Menu 1-27
Laser Safety Considerations 1-30
Accurate Measurements 1-33
Electrostatic Discharge Information 1-43
Quick Start 1-46
2 Measurement Techniques
The Calibrations 2-2
O/O Response and Isolation Bandwidth Calibration 2-5
O/E Response and Isolation Bandwidth Calibration 2-8
O/E Response and Match Bandwidth Calibration 2-11
E/O Response and Isolation Bandwidth Calibration 2-20
Agilent 86030A System Example Measurements 2-24
Electrical Mismatch Ripple and its Effects on Measurements. 2-25
Magnitude Response and Deviation From Linear Phase of a Lightwave
Receiver 2-37
O/E RF Overload Detection Measurement 2-47
3 Theory of Operation
System Operation 3-2
Lightwave Test Set Operation 3-3
Measurement Calibration 3-6
O/O Measurement Calibration 3-7
O/E Measurement Calibration 3-9
E/O Measurement Calibration 3-11
Electrical Measurement Calibration 3-13
O/E Display Scaling Calculations 3-14
E/O Display Scaling Calculations 3-15
Contents-1
Contents
O/O Display Scaling Calculations 3-16
4 Installation
Installation 4-2
Step 1. Prepare the site 4-4
Step 2. Install the monitor mount assembly 4-6
Step 3. Install the keyboard/mouse transmitter and the work surface 4-8
Step 4. Confirm front and rear panel connections 4-9
Step 5. Turn the system on 4-11
5 System Verification
Lightwave Verification 5-3
If the Lightwave Verification Test Fails 5-7
6 Maintenance
86032A Test Set Troubleshooting Diagnostics 6-6
Verifying the RF Path Integrity of the 86032A 6-12
Modulator Troubleshooting Tips 6-16
Agilent Technologies Support and Maintenance 6-17
Electrostatic Discharge Information 6-19
Returning the System for Service 6-22
Agilent Technologies Sales and Service Offices 6-25
After Repair 6-26
7 Specifications and Regulatory Information
General Specifications 7-3
Electrical Specifications 7-4
Optical to Optical (O/O) Specifications 7-6
Optical to Electrical (O/E) Specifications 7-7
Electrical to Optical (E/O) Specifications 7-12
Characteristics 7-16
Optical to Electrical (O/E) Characteristics 7-18
Electrical to Optical (E/O) Characteristics 7-21
Regulatory Information 7-24
Declaration of Conformity 7-25
Contents-2
1
“Front Panel Features” on page 1-8
“Rear Panel Features” on page 1-11
“Software Overview” on page 1-12
“File Menu” on page 1-13
“Options Menu” on page 1-20
“Tools Menu” on page 1-27
“Laser Safety Considerations” on page 1-30
“Accurate Measurements” on page 1-33
“Electrostatic Discharge Information” on page 1-43
“Quick Start” on page 1-46
Getting Started
Getting Started
System Overview
System Overview
The Agilent 86030A 50 GHz lightwave component analyzer provides accurate
and repeatable characterization of electro-optical, optical, and electrical components.
Components such as O/E photodiode receivers, E/O photodiodes, lightwave
modulators, and other optical and electrical components used in 40 Gb/s lightwave systems can be characterized in either a research and development or
manufacturing environment.
The Agilent 86030A system consists of an Agilent 85107B vector network analyzer system, an 86032A 50 GHz lightwave test set, system software, and a
personal computer serving as the system controller.
1-2
Getting Started
System Overview
1-3
Getting Started
System Overview
Calibrated Measurements
One of the key benefits of the 50 GHz lightwave component analyzer is its ability to perform calibrated measurements of optical components. The system
contains an O/E receiver that has been factory calibrated in magnitude, and
characterized in phase. The ability to make calibrated measurements assures
accuracy, reliability, and confidence in the components being measured. Additionally, the laser source, optical modulator, and calibrated O/E receiver are
temperature stabilized which also improves the accuracy and repeatability of
measurements.
Verification Device
A verification device is included with the system. It consists on an Agilent
83440D O/E photodetector and its associated amplitude and phase data. This
verification device can be used at any time to verify the measurement integrity
of your system. A guided verification routine is provided which measures the
verification device, and displays a graph of its response versus acceptable tolerances. The verification device can be used periodically to monitor system
calibration, and indicate when the optical test set needs to be recalibrated. It
can also be used to resolve uncertainty if unexpected results are obtained
from a test device. This verification capability provides confidence in the measurement integrity of the system.
Measurement Software
Guided measurement software provides an easy-to-use operator interface. It
provides pictorial diagrams of interconnections for configuration, calibration,
and measurements. On-screen prompts also guide you through the entire
measurement process, from the calibration to the measurement.
Data Management
Display, analysis, and archiving of data is easy and straightforward with the
system. The measured data is displayed on the Agilent 8510C network analyzer. Full use of the analyzer’s functions such as markers, data formats, and
data scaling features are available. Data can be archived to disk in either ASCII
text or Microsoft Excel formats. The include Excel software allows data to be
displayed and analyzed using standard Excel features and formats. Data connectivity to a local area network (LAN) is provided via a LAN card in the system’s PC.
1-4
Accessories Supplied
The accessories described below are shipped with your system.
Table 1-1. System Accessories
Description Agilent Model/Part Number Quantity
86030A Verification Kit
0 to 32 GHz Light Wave Detector 83440D 1
Cable Assembly 86030-60005 1
Power Supply 87421A 1
Reference Reflector Cable Assembly 81000BR 1
System Software Disk Set 86030-10001 1
Fiber Optic 4M Cable 1005-0173 3
Getting Started
System Overview
BNC Termination 1250-0207 2
6 dB (2.4 mm) Attenuator 8490D Opt 006 1
50 ohm load (2.4 mm) F 00901-60004 1
Adapter (2.4 mm), F/F 85056-60006 1
Other Accessories
86030A User’s Guide 86030-90001 1
2.4 mm 8510C Calibration Kit 85056A
2.4 mm Flexible Cables 85133F
1-5
Getting Started
Configuration Options
Configuration Options
The standard Agilent/HP 86030A system is supplied with FC/PC optical connectors. If other optical connectors are desired, ordering one of the following
connector options will replace the FC/PC connectors with the desired optical
connectors.
Table 1-2. Available Options for the 86032A System
Option Number Description
011 Diamond HMS-10 connector interface
013 DIN 47256 connector interface
014 ST optical connector interface
017 SC optical connector interface
Other Options
230 220-240 VAC operation
UK6 Test data for ISO 9001/2 commercial calibration
WARNING During measurements, laser light emits from the front-panel OPTICAL
OUTPUT connector and the LASER OUTPUT connector. This light
originates from the system’s laser source. Always keep these
connectors covered when not in use.
1-6
Getting Started
Configuration Options
CAUTION The warranty and calibration will be voided on systems where the individual
instruments are removed by the customer. The system should only be
disassembled by a Agilent Technologies Customer Engineer. Instruments
should not be replaced by non Agilent Technologies personnel.
Measurement accuracy—it’s up to you!
Fiber-optic connectors are easily damaged when connected to dirty or damaged cables
and accessories. The 86030A’s front-panel SOURCE OUTPUT and RECEIVER INPUT con-
nectors, 86032A Laser Output and External Laser Input are no exception. When you use
improper cleaning and handling techniques, you risk expensive instrument repairs, damaged cables, and compromised measurements. Before you connect any electrical cable
to the 86030A, refer to “Electrostatic Discharge Information” on page 6-19.
1-7
Getting Started
Front Panel Features
Front Panel Features
Figure 1-1. 86032A Front Panel
1-8
Getting Started
Front Panel Features
1. LASER Key Turns the laser on and off. Note that the laser is not operational
until it is activated by the 86030A software program. You can turn
on the laser manually from the Diagnostic software. From the
Windows Start menu, select Programs, Agilent Technologies 50
GHz LCA, 50 GHz Diagnostics. From the Laser menu, click Laser
ON. Make sure the laser key on the 86032A is in the on position.
WARNING Do NOT, under any circumstances, look into the optical output or any
fiber/device attached to the output while the laser is in operation.
Refer to “Laser Safety Considerations” on page 1-30.
2. Laser LED Indicates the state of the laser. When the LED is lit, the laser is
on. Note that the laser is not operational until it is activated by
the 86030A software program. You can turn on the laser manually
from the Diagnostic software. From the Windows Start menu,
select Programs, Agilent Technologies 50 GHz LCA, 50 GHz
Diagnostics. From the Laser menu, click Laser ON.
3. E/O LED When on, indicates the internal measurement path is selected for
an E/O (electrical-to-optical) device.
4. E/E LED When on, the internal measurement path is selected for an E/E
(electrical-to-electrical) device. The test set is in a bypass mode
for E/E device selection and the laser is shut down. The test set
will need to be in the ON position for use in E/E mode.
5. O/E LED When on, the internal measurement path is selected for an
(optical-to-electrical) O/E device.
6. O/O LED When on, the internal measurement path is selected for an
(optical-to-optical) O/O device.
7. DIRECTIONAL COUPLER
INPUT
8. DIRECTIONAL COUPLER
COUPLED
9. DIRECTIONAL COUPLER
TEST PORT
10. Grounding Receptacle Ground path that is provided to connect a static strap.
11. RF OUTPUT RF output that provides RF drive power for E/O devices.
12. OPTICAL RECEIVER RF
OUTPUT
Input for the optical direction coupler. This port is usually
connected to the OPTICAL OUTPUT.
Port for the coupler output. This port is usually connected to the
OPTICAL RECEIVER INPUT.
Coupler output port (transmission) or test port (reflection).
Test set optical receiver output
1-9
Getting Started
Front Panel Features
13.OPTICAL RECEIVER
INPUT
14. OPTICAL OUTPUT Modulator output.
15. LASER INPUT External laser input
16. LASER OUTPUT Output of internal laser
17. POWER Switch Turns the instrument power on.
Test set optical receiver input
CAUTION Use care in handling optical connectors. Damage to an optical test port
connector can require a costly repair and lost productivity for the system. Keep
optical cables connected to the test ports to protect the connectors from
damage. Also, make sure to clean the connectors before each use. Refer to
“Accurate Measurements” on page 1-33.
1-10
Rear Panel Features
Getting Started
Rear Panel Features
Figure 1-2. 86032A Rear Panel
1. Remote Programming
Connector
2. Laser Remote Shutdown Turns the laser on or off. When the BNC short is connected, the
3. Line Module This assembly houses the line cord connector.
4. RF REF OUTPUT RF output of the test set that is used to route the 8517B electrical
5. EXT ALC DC output from the levelling detector on the internal ALC circuit.
6. RF INPUT RF input port from the source output of the network analyzer.
Allows for remote control of the instrument’s front panel via the
86030A software installed on the system PC.
laser is enabled. When removed, the laser is disabled.
test set for phase locking.
This output is routed to the EXT ALC port of the network analyzer
source.
1-11
Getting Started
Software Overview
Software Overview
The 86030A software sets up instrument states on the network analyzer and
lightwave test set, and guides you through the measurement calibration and
measurement procedures. The program combines the measurement calibration traces with the calibration data response of the lightwave receiver, and
loads the result back into the network analyzer to provide calibrated lightwave
measurements. You can save and view trace data using Microsoft Excel, and
manually control the 86032A test set operation.
1-12
Getting Started
File Menu
File Menu
The File menu is used to save data as either an ASCII text file or an Excel
worksheet. Using Graph Excel Data allows you to automatically view saved
data in an Excel worksheet as tabular data, or as graphical data in log magnitude, phase or delay formats. The File menu is also used to exit the application.
Save Data
Text File Text File allows you to save data as an ASCII text file in four different formats:
Raw Data, Log Magnitude, Phase, or Delay.
1-13
Getting Started
File Menu
Raw Data saves trace data in a ASCII text format (.txt) known as a CITIFile
(common instrumentation transfer and interchange file). The CITIFile format
is useful when data will be exchanged with another network analyzer. The
data file saves both real and imaginary pairs independent of the format of the
active screen. However, any trace smoothing that was applied to the measurement will not be saved (that is, Smoothing On is activated from the 8510C
Response menu).
Formatted Data, Log Mag, Phase, Delay saves trace data with any trace
smoothing that was applied to the measurement (that is, Smoothing On is activated from the 8510C Response menu), but only retains the values of the format that was selected for saving (that is, Log Magnitude, Phase, or Delay).
Excel File Excel File allows you to save the trace display as a Microsoft Excel workbook
(.xls extension). The Excel format is useful when you want to view or edit the
data in an Excel spreadsheet.
Raw Data saves both real and imaginary pairs independent of the format of
the active screen. This data can later be viewed in either Log Magnitude or
Phase format from the File, Graph Excel Data menu. Any trace smoothing that
was applied to the measurement will not be saved (that is, if Smoothing On is
activated from the 8510C Response menu).
Formatted Data saves trace data and any trace smoothing that was applied
to the measurement, but only viewed using the format that the data was originally saved (that is, Log Magnitude, Phase, or Delay).
1-14
Getting Started
File Menu
Log Mag saves the log magnitude format. This is the standard Cartesian format used to display magnitude-only measurements of insertion loss, return
loss, or absolute power in dB versus frequency.
Phase saves the phase of data versus frequency in a Cartesian format.
Delay saves the group delay format, with marker values given in seconds.
Group delay is the measurement of signal transmission time through a test
device. It is defined as the derivative of the phase characteristic with respect
to frequency. Since the derivative is basically the instantaneous slope (or rate
of change of phase with frequency), a perfectly linear phase shift results in a
constant slope, and therefore a constant group delay.
Graph Excel Data
Raw Data Data allows you to view trace data in either Log Magnitude or Phase format.
However, any trace smoothing that was applied to the measurement will not
be captured. (that is, if Smoothing On was activated from the 8510C Response
menu).
Log Magnitude displays the trace data in Cartesian format as logarithmic
(dB) magnitude versus frequency.
Phase displays the trace data in Cartesian format as phase versus frequency.
Formatted Data, Formatted Data allows you to view trace data in the format that it was saved
(that is, Log Magnitude, Phase, or Delay) including any trace smoothing that
was applied to the measurement
1-15
Getting Started
File Menu
Log Mag displays the log magnitude format. This is the standard Cartesian
format used to display magnitude-only measurements of insertion loss, return
loss, or absolute power in dB versus frequency.
Phase displays the phase shift of data versus frequency in a Cartesian format.
Delay displays the group delay format, with marker values given in seconds.
Group delay is the measurement of signal transmission time through a test
device. It is defined as the derivative of the phase characteristic with respect
to frequency. Since the derivative is basically the instantaneous slope (or rate
of change of phase with frequency), a perfectly linear phase shift results in a
constant slope, and therefore a constant group delay. Figure 1-3
Figure 1-3.
Note, however, that the phase characteristic typically consists of both linear
and higher order (deviations from linear) components. The linear component
can be attributed to the electrical length of the test device, and represents the
average signal transit time. The higher order components are interpreted as
variations in transit time for different frequencies, and represent a source of
signal distortion. See Figure 1-4.
1-16
Figure 1-4.
Getting Started
File Menu
Group Delay τ
Gφ
J
Gω
in Radians
in Radians
1
360°
Gφ
⋅
GI
φ in Degrees
I in Hz (ω 2πI )
The analyzer computes group delay from the phase slope. Phase data is used
to find the phase change, ∆φ, over a specified frequency aperture, ∆ƒ, to
obtain an approximation for the rate of change of phase with frequency (Fig-
ure 1-5). This value, τ
, represents the group delay in seconds assuming linear
g
phase change over ∆ƒ. It is important that ∆φ be ≤180°, or errors will result in
the group delay data. These errors can be significant for long delay devices.
Figure 1-5.
When deviations from linear phase are present, changing the frequency step
can result in different values for group delay. Note that in this case the computed slope varies as the aperture ∆ƒ is increased (Figure 1-6). A wider aper-
1-17
Getting Started
File Menu
ture results in loss of the fine grain variations in group delay. This loss of detail
is the reason that in any comparison of group delay data it is important to
know the aperture used to make the measurement.
Figure 1-6.
In determining the group delay aperture, there is a trade-off between resolution of fine detail and the effects of noise. Noise can be reduced by increasing
the aperture, but this will tend to smooth out the find detail. More detail will
become visible as the aperture is decreased, but the noise will also increase,
possibly to the point of obscuring the detail. A good practice is to use a smaller
aperture to assure that small variations are not missed, then increase the aperture to smooth the trace.
1-18
Exit
Exit closes the 86030A software application.
Getting Started
File Menu
1-19
Getting Started
Options Menu
Options Menu
The Options menu allows you to set and monitor system functions.
Auto Bias
Auto Bias allows you bias the modulator to operate at quadrature or at maximum optical power. Under typical circumstances the lightwave modulator is
biased to operate at quadrature. Quadrature is the point where the slope of
the optical power versus voltage is maximally positive. Refer to Figure .
1-20
Getting Started
Options Menu
Power at
Quadrature (1)
Voltage at
Quadrature (2)
Figure 1-7. Effect of Bias Voltage on Modulated Optical Power
The power where the optical power versus bias voltage slope is maximum for a
positive slope.
The voltage where the optical power versus bias voltage slope is maximum for
a positive slope.
1-21
Getting Started
Options Menu
Voltage at
Maximum Optical
Power (3)
Voltage at
Minimum Optical
Power (4)
Maximum Optical
Power (5)
Minimum Optical
Power (6)
The voltage at which the maximum output power occurs (V
The voltage at which the minimum output power occurs (V
min
max
).
).
The maximum output power.
The minimum output power.
How to Determine if Auto Bias Values are Reasonable
The following formulas will help you to determine if the modulator auto bias
settings are valid. Refer to Figure .
Voltage at Maximum Optical Power – Voltage at Minimum Optical Power
should between 3 and 6 volts.
Voltage at Quadrature should be approximately
Maximum Optical Power should be > 3 dBm
Power at Quadrature should be > 0dBm
Tip: You can set the this value manually. From the Tools menu, click on Moni-
tor Test Set. In the Modify Bias Voltage text box, enter the desired value and
then click Set Modulator Bias Voltage to.
Refer to “Modulator Troubleshooting Tips” on page 6-16 for more information.
9PD[ 9PLQ
2
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Getting Started
Options Menu
Auto Bias At Cal
Auto Bias At Cal when selected, an auto bias is performed before each calibration. The auto bias is performed after you click either Resp Cal or Resp-Isol
Cal.
Customize
Customize allows you to set and monitor certain parameters that affect the
operation of the system.
Standard The Standard Settings dialog box allows you to set and monitor certain param-
eters controlled by the network analyzer.
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Getting Started
Options Menu
GPIB Address displays the current address setting for the analyzer. This
value must correspond to the actual address on the 8510 GPIB address bus.
Failure of these two numbers to match will prevent operation.
Average Factor is used to improve the sensitivity of the measurement. For
the Step Mode of operation for each modulation frequency point, multiple
data point samples (equal to the number of averages) are measured by the
system, and averaged together to provide a single average value. Averaging
multiple data points together reduces the effects of noise on the measurement. The improvement in sensitivity is equal to:
10
log number of averages
10
Note the 8510C network analyzer only averages with powers of 2 (that is, 1, 2,
4, 8, 16, 32, 64, 128, 256, 512, 1024, and so on). Therefore, if an averaging factor of 500 is set on the analyzer, the analyzer will default to 256 averages.
Bias Interval, mins corresponds to the number of minutes before prompting
you to perform another modulator auto bias.
Refl Standard% corresponds to the percent of reflection of the Reflection
Standard used in the system. This is useful for O/O reflection modes.
Averaging when selected, the network analyzer will perform averaging at
each data point.
Split Screen E/O when selected, the network analyzer displays both the
bandwidth and reflection measurement on the display. This function is only
valid with an E/O Bandwidth and Reflection measurement. Bandwidth is
displayed on channel 1 and Reflection is displayed on channel 2. When this
function is cleared, use the network analyzer front panel channel buttons to
select between the two measurements.
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