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USA
For product information, sales, service, and technical support:
In North America, call 1-800-833-9200.
Worldwide, visit www.tektronix.com to find contacts in your area.
Page 3
Warranty 2
Tektronix warrants that this product will be free from defects in materials and workmanship for a period of one (1) year
from the date of shipment. If any such product proves defective during this warranty period, Tektronix, at its option,
either will repair the defective product without charge for parts and labor, or will provide a replacement in exchange
for the defective product. Parts, modules and replacement products used by Tektronix for warranty work may be new
or reconditioned to like new performance. All replaced parts, modules and products become the property of Tektronix.
In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration of
the warranty period and make suitable arrangements for the performance of service. Customer shall be responsible for
packaging and shipping the defective product to the service center designated by Tektronix, with shipping charges
prepaid. Tektronix shall pay for the return of the product to Customer if the shipment is to a location within the country
in which the Tektronix service center is located. Customer shall be responsible for paying all shipping charges, duties,
taxes, and any other charges for products returned to any other locations.
This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate
maintenance and care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage
resulting from attempts by personnel other than Tektronix representatives to install, repair or service the product; b) to
repair damage resulting from improper use or connection to incompatible equipment; c) to repair any damage or
malfunction caused by the use of non-Tektronix supplies; or d) to service a product that has been modified or integrated
with other products when the effect of such modification or integration increases the time or difficulty of servicing the
product.
THIS WARRANTY IS GIVEN BY TEKTRONIX WITH RESPECT TO THE PRODUCT IN LIEU OF ANY OTHER
WARRANTIES, EXPRESS OR IMPLIED. TEKTRONIX AND ITS VENDORS DISCLAIM ANY IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. TEKTRONIX’
RESPONSIBILITY TO REPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE AND EXCLUSIVE
REMEDY PROVIDED TO THE CUSTOMER FOR BREACH OF THIS WARRANTY. TEKTRONIX AND ITS
VENDORS WILL NOT BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL
DAMAGES IRRESPECTIVE OF WHETHER TEKTRONIX OR THE VENDOR HAS ADVANCE NOTICE OF
THE POSSIBILITY OF SUCH DAMAGES.
This manual provides operating instructions for the RSA3408B Real-Time
Spectrum Analyzer Option 29 WLAN 802.11a/b/g/n Analysis Software.
This manual supports the following instrument:
RSA3408B Option 29
This manual is composed of the following sections:
Getting Started provides overviews of the product and its functions.
Operating Basics provides information needed for routine operation.
Reference describes the measurement procedure, setup menu, and view format
specific to Option 29 in detail.
Appendices provides additional information, including the scale setting range
and save file format.
The analyzer uses Microsoft Windows XP as the operating system. This manual
does not describe common usage of Windows XP. Refer to your Windows manuals
as necessary.
RSA3408B Option 29 User Manual
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Page 12
Preface
Related Manuals
The following related documents are also available:
RSA3408B User Manual
(Standard accessory; Tektronix part number 071-2364-XX)
Describes how to install the analyzer and how to work with the menus, and
details the standard functions. Also shows the specifications.
RSA3000B Series Programmer Manual
(Standard accessory; PDF, Tektronix part number 071-2382-XX)
Contains an alphabetical listing of the programming commands and other
information related to controlling the analyzer over the GPIB interface.
PDF Manual
The RSA3000B Series Programmer Manual (PDF only) is included in the
Documents CD (Tektronix part number 063-4089-XX).
viii
RSA3408B Option 29 User Manual
Page 13
Getting Started
Page 14
Page 15
Getting Started
The RSA3408B Option 29 is the WLAN 802.11a/b/g/n analysis software that
performs signal measurements for high-speed wireless LAN transmitters in 5 GHz
and 2.4 GHz bands complying with the IEEE802.11 a, b, g, and n standards.
Table 1-1 summarizes the IEEE802.11 standards.
This software is compliant with Draft 11n as of December 2006.
Figure 1-1 shows a typical display example of WLAN analysis.
Figure 1-1: WLAN analysis display
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Getting Started
Measurement Items
Table 1-2 shows all the measurement and display items available in Option 29
WLAN analysis software and the supported standards. The measurement items are
classified into Modulation measurement and Power measurement.
Table 1-2: Option 29 WLAN measurement items
Measurement
Measure menu item
Modulation measurement
Transfer Function
(Amplitude and Phase)
Delay ProfileTransfer Efficiency
versus Time
EVM versus TimeEVM
Power versus TimeConstellationTransfer Efficiency
versus SC
EVM versus SCEVM
Power versus SCSC ConstellationFrequency ErrorOFDM FlatnessOFDM LinearitySymbol Table-
Power measurement
Spectrum MaskTransmit Power-
Abbreviation. Err: Error; Mag: Magnitude; SC: Subcarrier. Refer to
For the 802.11n standard, this software is compliant with Draft 11n as of
December 2006.
RSA3408B Option 29 User Manual
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Signal Format in IEEE802.11n Analysis
Transmission
SISO 1x1 (one Tx antenna and one Rx antenna)
802.11n (nx1) analysis
Reception
Transmission
MISO 2x1 (two Tx antennas and one Rx antenna)
Reception
Transmission
MIMO 2x2 (two Tx antennas and two Rx antennas)
802.11n MIMO (2x2) analysis
Reception
Antenna
OutputPropagation pathInput
IEEE802.11n analysis consists of 802.11n (nx1) and MIMO (2x2) analyses,
supporting three signal formats as shown in Figure 1-2.
Getting Started
Figure 1-2: Signal format in IEEE802.11n analysis
MIMO (Multi-Input Multi-Output) uses more than one antennas for both
transmitting and receiving to transfer data at the same time. Radio signals input
from the transmitter go through multiple propagation paths and output to the
receiver. Multiple antennas send and receive different data streams simultaneously
over multiple paths as independent channels, resulting in a higher transmission rate
along with the number of antennas. Special, degenerated cases of MIMO are
MISO (Multi-Input Single-Output) when the receive antenna is single, and
SISO (Single-Input Single-Output) when both transmit and receive antennas
are traditionally single. The Option 29 WLAN analysis software supports three
signal formats: SISO 1x1, MISO 2x1, and MIMO 2x2.
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Page 18
Getting Started
Analyzable Signals
In IEEE802.11n analysis, the analyzable signals vary between the 1x1, 2x1, and
2x2 measurement modes.
NOTE.
This software supports only the Direct mapping as the spatial mapping
method for MIMO signals. The analyzer cannot properly demodulate signals of the
Spatial expansion and Beam forming.
1x1.
The 11n SISO signals including 802.11b/g (DSSS, CCK, PBCC) can be
analyzed. In this mode, the sync timing is calculated accurately using STF (Short
Training Field) to analyze the OFDM preamble part. It is effective for the
measurements with the analyzer connected directly to the transmitter. But in such
a multi-path environment as the transfer function flatness degrades, the analyzer
may not synchronize properly.
2x1.
The 11n SISO signals excluding 802.11b/g, STBC (Nss=1, Nsts=2) signals,
and MIMO signals of Direct Mapping (Nss=2, Nsts=2) can be analyzed.
For MIMO signals, the data part can be analyzed with the analyzer inputting only
one-channel transmit signal directly. When inputting a two-channel mixed signal,
the data part cannot be demodulated properly, but the transfer function and
delay profile can be calculated.
In the 2x1 mode, the sync timing is not calculated accurately to analyze the
OFDM preamble part for processing multi-channel mixed signals. So the
measurement result, such as EVM of STF (Short Training Field) and LTF (Long
Training Field) may degrade.
1-4
2x2.
The 11n SISO signals excluding 802.11b/g, STBC (Nss=1, Nsts=2) signals,
and MIMO signals of Direct Mapping (Nss=2, Nsts=2) can be analyzed.
Table 1-3 summarizes the analyzable signals for each measurement mode.
Table 1-3: Analyzable signals with the 802.11n measurement modes
Only for one-channel direct connection, or the transfer function and delay profile displays.
1x12x12x2
✓
✓ ✓ ✓
✓ ✓
1
✓
✓
RSA3408B Option 29 User Manual
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Standard...IEEE802.11a/b/gEVM vs Time
Power vs Time
Constellation
EVM vs SC
Power vs SC
SC Constellation
Frequency Error
OFDM Flatness
OFDM Linearity
Symbol Table
Spectrum Mask
Tra n s m i t Po w e r
Mode
S/A
Demod
Time
Measure menu items
802.11n (nx1)Transfer Function (Amp)
Transfer Function (Phase)
Delay Profile
EVM vs Time
Power vs Time
Constellation
EVM vs SC
Power vs SC
SC Constellation
Frequency Error
OFDM Flatness
OFDM Linearity
Symbol Table
Spectrum Mask
802.11n MIMO (2x2)Transfer Function (Amp)
Transfer Function (Phase)
Delay Profile
Transfer Efficiency vs Time
EVM vs Time
Power vs Time
Constellation
Transfer Efficiency vs SC
EVM vs SC
Power vs SC
SC Constellation
Frequency Error
Symbol Table
Getting Started
Accessing the Measurements
The Option 29 WLAN measurement functions are contained in the Demod mode
as shown in Figure 1-3. The analysis is categorized into three groups: IEEE
802.11a/b/g, 802.11n (nx1, Multi-Input Single-Output), and 802.11n MIMO
(Multi-Input Multi-Output, 2x2).
Figure 1-3: Measure menu in the WLAN analysis
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Getting Started
1-6
RSA3408B Option 29 User Manual
Page 21
Operating Basics
Page 22
Page 23
Operating Basics
This section describes the basic operation specific to the WLAN analysis with the
following topics:
Screen Elements
Setting Frequency and Span
Setting Acquisition and Analysis Parameters
View Operation
Saving Measurement Results and Loading Waveform Data
NOTE.
Manual.
For complete details on operating the analyzer, refer to the RSA3408B User
RSA3408B Option 29 User Manual
2-1
Page 24
Operating Basics
Side menu
Trigger status
SubviewOverview
Main view
Current setting
Hardware setting
Screen Elements
Figure 2-1 shows the screen elements of the WLAN analysis. The analysis runs in
the Demod (modulation analysis) mode and displays the following three views on
the screen. The spectrum mask measurement is an exception; it uses a single view
like the S/A (Spectrum Analyzer) mode.
Overview. Displays all data in one acquisition block. Use this overview to set
the acquisition and analysis parameters such as acquisition length and analysis
length (refer to Setting Acquisition and Analysis Parameters on page 2-6).
Main view. Displays the measurement results and waveform for the range
specified in the overview.
Subview. Displays the spectrum (by default) for the range specified in the
overview. You can select the view content with the View Define menu.
For details on setting the views, refer to View Operatio n on page 2-7.
2-2
Figure 2-1: Screen elements
RSA3408B Option 29 User Manual
Page 25
Setting Frequency and Span
Use the Frequency/Channel and the Span keys on the front panel to set frequency
and span. For WLAN analysis, you can use the channel tables shown in Table 2-1.
The span setting depends on the measurement item as shown in Table 2-2.
Table 2-2: Span setting
Analysis typeMeasurement itemSpan
Modulation analysisTransfer Function20 or 36 MHz
Delay Profile
Transfer Efficiency versus Time
EVM versus Time
Power versus Time
Constellation
Transfer Efficiency versus SC
EVM versus SC
Power versus SC
SC Constellation
Frequency Error
OFDM Flatness
OFDM Linearity
Symbol Table
Power analysisSpectrum Mask100 MHz to 3 GHz
Transmit Power20 or 36 MHz
(The default is 36 MHz)
(The default is 36 MHz)
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Operating Basics
Overview
Acquisition Length
Analysis Length
Analysis Offset
Spectrum Offset
Output Trigger Indicator
Acquisition History
The data in the analysis range
(indicated by the green lines) is
analyzed and the result is
displayed in the main view.
Setting Acquisition and Analysis Parameters
Press the Acquisition/Analysis key to set the acquisition and analysis parameters
described below on the overview (see Figure 2-2).
Acquisition Length.
Acquisition History.
Spectrum Length.
Spectrum Offset.
Analysis Length.
Analysis Offset.
Output Trigger Indicator.
Sets the time to acquire one block.
Specifies the number of the block to analyze and display.
Shows time for FFT to display spectrum in the subview.
Sets the beginning of Spectrum Length.
Sets the analysis range in time units (max. 100 ms).
Sets the beginning of Analysis Length.
Turns on or off the output trigger indicator.
For details on setting the timing and trigger, refer to the RSA3408B User Manual.
2-6
Figure 2-2: Acquisition and analysis parameters
NOTE.
The Timing menu is not available in the Spectrum Mask measurement.
Only Acquisition Length is available in the Transmit Power measurement.
RSA3408B Option 29 User Manual
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View Operation
Operating Basics
This section provides view operating basics, addressing the following topics:
Changing the View Content
Selecting the Phase Unit
Scaling the Graph
Changing the View Content
Selecting the Phase Unit
You can change the view content with the View: Define key on the front panel.
The View Define menu has the following controls.
Show Views.
Single. Displays one view on screen.
Selects the single or multi view.
Select the view with the View: Select key.
Multi. Displays the overview, the main view, and the subview on screen.
Overview Content...
Subview Content...
Selects the overview content.
Selects the subview content.
The view contents depend on the measurement items. Refer to each
The phase unit in the EVM measurement defaults to degrees. You can select
degrees or radians using the following steps:
1. Press the System key.
2. Press the Instrument Setup... side key.
3. Press the Angular Units side key to select Degrees or Radians.
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Operating Basics
Horizontal Scale
Horizontal Start
Ver tica l S c ale
Vertical Start
Ver t i ca l S t o p
Vertical Offset
Scaling the Graph
You can expand a waveform horizontally and vertically pressing View: Scale/Lines →View Scale... (you cannot compress the original waveform). The scale setting
affects only the display; it does not change the acquisition parameters such as
span, center frequency, and reference level. Although the Scale menu varies with
the measurement items, it has commonly the following controls as shown in
Figure 2-3.
Horizontal Scale.
Horizontal Start.
Vertical Scale.
Vertical Start.
Vertical Offset.
Vertical Stop.
Sets the range of the horizontal axis.
Sets the minimum value (left edge) of the horizontal axis.
Sets the range of the vertical axis.
Sets the minimum value (bottom edge) of the vertical axis.
Sets the center value of the vertical axis.
Sets the maximum value (top edge) of the vertical axis.
2-8
Figure 2-3: Definition of the View Scale menu items
Press the View: Select key to select a view before scaling the graph pressing View:
Scale/Lines → View Scale.... Chapter 3, Reference, describes the Scale menu for
each measurement item. Refer to the following sections:
IEEE802.11a/b/g Analysis: View Format on page 3-11
IEEE802.11n (nx1) Analysis: View Format on page 3-55
IEEE802.11n MIMO (2x2) Analysis: View Format on page 3-102
RSA3408B Option 29 User Manual
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Saving Measurement Results and Loading Waveform Data
Use the Save and Load keys on the front panel to save measurement results and
load waveform data to/from a file.
Operating Basics
Save Menu
NOTE.
This section provides information about file save specific to Option 29
WLAN analysis. For details on standard file operations, refer to the RSA3408B
User Manual.
The Save menu for the modulation measurements has the following controls.
Save State.
Save Data... / Data (.CSV)... / Data (.MAT)...
Saves the instrument settings.
Saves the input waveform (IQ data in the
time domain) to a file in the IQT, CSV (Comma Separated Values), or
MATLAB format, respectively. You can export the CSV file into Microsoft Excel
or other database systems and the MAT file into the MATLAB technical computing
environment.
All Blocks. IQT format only. Saves all the acquired blocks.
Current Block. Saves the block currently displayed in the overview.
Current Area. Saves the data in the analysis range.
Save Mainview Results.
802.11n (nx1) and MIMO (2x2) analyses only.
Saves the measurement results to a file in the CSV (Comma Separated Values)
format. You can export the file into Microsoft Excel or other database systems.
Refer to Appendix B for the save format.
Submenu items for the transfer function and delay profile measurements:
Trace 1. Saves Trace 1 to a specified file.
Trace 2. Saves Trace 2 to a specified file.
Trace 1 and 2. Saves Trace 1 and 2 to two files with the file names of “1” and
All Data. MIMO (2x2) analysis only. Saves Trace 1 and 2 to a specified file in
Packets Offset. Specifies the first packet to save. (See Figure 2-4.)
Number of Packets. Sets the number of packets to save. (See Figure 2-4.)
RSA3408B Option 29 User Manual
“2” added respectively to a specified name.
all combinations of the Tx and Rx antennas.
Range: −[(the number of packets in the analysis range) − 1] to 0.
Zero (0) represents the latest packet.
Range: 1 to [−(Packet Offset) + 1].
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Operating Basics
Packet
0
−
1
−
2
−
n
……
Number of Packets
Packets Offset
Saved to a file
File name: “Example.iqt”
Displayed normally.
File name: “ExampleOfLongName withSpaces Inserted.iqt”
Only the part within the allowable range is displayed with line feed
inserted at space. The third and the subsequent lines are omitted.
Figure 2-4: Setting packets to be saved
Submenu items for other than transfer function and delay profile measurements
(MIMO (2x2) analysis only):
Trace Data . Saves the displayed trace data to a specified file.
All Data. Saves the trace data to a specified file in all combinations of the Tx
and Rx antennas.
Load Menu
Displaying File Name
The Load menu for the modulation measurements has the following controls.
Load State.
Load Data.
Loads the instrument settings.
802.11n (nx1) analysis only.
Loads the input waveform (IQ data in the time domain) from a file (.iqt).
Load Rx1 / Load Rx2.
802.11n MIMO (2x2) analysis only.
Loads the receiving antenna 1 and 2 input waveform (IQ data in the time domain)
from a file (.iqt), respectively.
When you load an .iqt file, the file name appears on the Load Data / Rx1 / Rx2
side key. Because of the limitation of display area, if the number of characters
exceed the limit, only the part within the allowable range will be displayed with
line feed inserted at space if any (see Figure 2-5).
2-10
Figure 2-5: Displaying the file name on the Load Data / Rx1 / Rx2 side key
RSA3408B Option 29 User Manual
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Reference
Page 34
Page 35
IEEE802.11a/b/g Analysis
Standard...IEEE802.11a/b/g
Measure menu items
Modulation measurement
EVM versus Time
Power versus Time
Constellation
EVM versus SC
Power versus SC
SC Constellation
Frequency Error
OFDM Flatness
OFDM Linearity
Symbol Table
Power measurement
Spectrum Mask
Transmit Power
Mode
S/A
Demod
Time
This section describes the basic operation of the IEEE802.11a/b/g analysis.
You can access the measurement items by pressing Demod → Standard... → IEEE802.11a/b/g as shown in Figure 3-1.
Figure 3-1: IEEE802.11a/b/g measurement menu
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IEEE802.11a/b/g Analysis
Basic Measurement Procedure
The basic measurement procedures are described for the modulation analysis and
the power analysis.
Modulation Measurement
Follow these steps to perform the modulation measurement.
1. Press Demod → Standard... → IEEE 802.11a/b/g.
2. Set frequency and span appropriately using the Frequency/Channel and the
Span keys. Refer to Setting Frequency and Span on page 2-3.
3. Set the amplitude appropriately using the Amplitude key.
NOTE.
will be displayed in the red box at the center top of the screen. In this case, raise
the reference level.
4. Press the Acquisition/Analysis key and set the acquisition and analysis
5. After acquiring measurement data, stop the data acquisition using the
6. Press the Measure key and select the measurement item.
7. Press Meas Setup → Analysis Parameter... to preset the parameters.
If the input signal level is too high, “Overrange - increase RefLev or Atten"
parameters. Refer to Setting Acquisition and Analysis Parameters on page 2-6.
Run/Stop key.
For example, press the Power vs Time side key to observe power variance.
a. Press the Modulation Detection... side key and select the modulation type
(data rate). The default setting is AUTO.
3-2
b.Select the Synchronization and Equalization options as necessary.
For details on setting the Measurement Setup menu, refer to page 3-5.
8. Press Meas Setup→ Analyze to start the analysis for the acquired data with
the specified parameters.
If you cancel the analysis, press the Cancel-Back (top) side key.
9. Use the View menu to modify the displayed graph.
For details on setting the views, refer to View Format on page 3-11.
RSA3408B Option 29 User Manual
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IEEE802.11a/b/g Analysis
Power Measurement
The power analysis consists of Spectrum Mask and Transmit Power.
Follow these steps to perform the power analysis.
1. Press Demod → Standard... → IEEE 802.11a/b/g.
2. Set frequency and span appropriately using the Frequency/Channel and the
Span keys. Refer to Setting Frequency and Span on page 2-3.
3. Set the amplitude appropriately using the Amplitude key.
NOTE.
will be displayed in the red box at the center top of the screen. In this case, raise
the reference level.
4. Transmit Power only. Press the Acquisition/Analysis key and set the
5. Press the Measure key and select the measurement item. For example, press
6. Press the Meas Setup key and set the measurement parameters.
7. Use the View menu to modify the displayed graph.
If the input signal level is too high, “Overrange - increase RefLev or Atten"
acquisition and analysis parameters. Refer to Setting Acquisition and Analysis
Param et er s on page 2-6.
the Spectrum Mask side key to observe the spectrum mask.
For details on setting the Measurement Setup menu, refer to page 3-4.
For details on setting the views, refer to View Format on page 3-11.
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IEEE802.11a/b/g Analysis
Meas Setup Menu
Press the Meas Setup key to set the measurement parameters. The Meas Setup
menu varies among the measurement items. Refer to the section shown in
Tab le 3-1 .
Table 3-1: Measurement setup reference for the 802.11a/b/g analysis
Measurement itemReference section
Modulation measurements
EVM versus Time
Power versus Time
Constellation
EVM versus SC
Power versus SC
SC Constellation
Frequency Error
OFDM Flatness
OFDM Linearity
Symbol Table
Power measurements
Spectrum MaskMeasurement Setup for Spectrum Mask on page 3-9
Transmit PowerMeasurement Setup for Transmit Power on page 3-10
Measurement Setup for Modulation Measurements
on page 3-5
3-4
RSA3408B Option 29 User Manual
Page 39
Measurement Setup for Modulation Measurements
The Meas Setup menu for the modulation measurements has the following
controls:
IEEE802.11a/b/g Analysis
Analyze
Analysis Parameter...
Performs the analysis for the input data in the range specified on the overview.
You need to set the analysis parameters before pressing the Analyze side key.
Modulation Detection...
Selects the demodulation type. If you select Auto, the
demodulation type will be determined dynamically by decoding the preamble.
LT S. Default. Synchronizes with Long Training Symbol.
GI. Synchronizes with Guard Interval.
Equalization.
long training symbol during the analysis.
On. Default. Enables the data correction.
Off. Disables the data correction.
RSA3408B Option 29 User Manual
Selects the synchronization method.
Determines whether to apply the data correction using the
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IEEE802.11a/b/g Analysis
Select Subcarrier...
Subcarrier #
Symbol #
Selects subcarrier for a displayed line graph.
Data + Pilot. Default. Displays the measurement results for data and pilot.
Data. Displays the measurement results for data only.
Pilot. Displays the measurement results for pilot only.
Single Subcarrier. Displays the measurement results for the subcarrier
specified using the Subcarrier # side key below.
Specifies the subcarrier number for the measurement. Range: −32 to +31.
The function varies by measurement as shown in Table 3-3.
Specifies the analysis symbol number for the measurement.
The function varies by measurement as shown in Table 3-3.
Range: −[(the number of symbols in the analysis range) − 1] to 0.
Zero (0) represents the latest analysis symbol.
NOTE.
For definition of the analysis symbol, refer to page 3-7.
The Select Subcarrier..., Subcarrier #, and Symbol # menu items are effective
only in the measurements shown in Table 3-3.
Table 3-3: Submenu availability
Measure menu itemSelect Subcarrier...Subcarrier #Symbol #
EVM versus Time D S M
Power versus Time D S M
Constellation D S M
EVM versus SC - M D
Power versus SC - M D
SC Constellation - M D
Frequency Error D S M
OFDM Flatness - M OFDM Linearity - - Symbol Table - M D
D: Changing the setting updates the measurement data.
M: Changing the setting updates the marker position.
S: Changing the setting updates the measurement data only when
Select Subcarrier is set to Single Subcarrier.
Abbreviation. SC: Subcarrier
3-6
RSA3408B Option 29 User Manual
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IEEE802.11a/b/g Analysis
Definition of the Analysis Symbol.
In the modulation analysis, it is important to
calculate average values of RMS voltage or center frequency error for enough time
to get good analysis results. The length of a signal to calculate the RMS voltage or
center frequency error is called “analysis symbol” in the WLAN analysis software.
For example, frequency error by the analysis symbol is displayed on the center
frequency error view. Although “symbol” is defined for OFDM in the 802.11a/g
standard, “analysis symbol” is used in the WLAN analysis software taking the
other modulation types into account.
The following views display the averaged values by analysis symbol for power,
EVM, magnitude error, and phase error, respectively.
Power versus Time
EVM versus Time
MagErr versus Time
PhaseErr versus Time
The following views display analysis results of power, EVM, magnitude error, and
phase error, respectively for each data point, chip, or subcarrier contained in one
analysis symbol.
Power versus SC
EVM versus SC
MagErr versus SC
PhaseErr versus SC
The length of an analysis symbol depends on the modulation type as follows:
Table 3-4: Length of an analysis symbol, IEEE802.11a/g
Part of a signalType of the signalLength of an analysis symbol
Data partOFDM80 sample points
DSSS88 chips
CCK80 chips
PBCC80 data points
Preamble/Header partShort OFDM training symbol16 sample points
Long OFDM training symbol160 sample points
PLCP preamble1584 chips
Short PLCP preamble792 chips
PLCP header528 chips
Short PLCP header264 chips
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IEEE802.11a/b/g Analysis
IEEE 802.11a IEEE 802.11b IEEE 802.11g
Preamble
Data
Select an item to change
the on/off setting.
Turn on or off the
selected item.
Turn on or off all the
preambles.
Turn on or off all the
data.
Modulation Type
Display Filter...
Selects the modulation type(s) to display the measurement results on the screen.
The results and graph are shown only for the types set to On.
Select cell to edit.
Selects an item to change the on/off setting in the table on screen.
The table consists of six blocks as shown in Figure 3-2. The selected item appears
on the second side key where you can turn it on or off.
All Preambles On/Off.
All Data On/Off.
Turns on or off all the preambles.
Turns on or off all the data.
Figure 3-2: Modulation Type Display Filter setting
3-8
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Measurement Setup for Spectrum Mask
Transmit spectrum mask
Unfiltered Sinx/x
Frequency (MHz)
-22
Power spectral density
-1101122
0 dB
-30 dB
-50 dB
DSSS (IEEE802.11b)
OFDM (IEEE802.11a)
Power spectral density
Transmit spectrum mask
Typical signal spectrum
Frequency (MHz)
-20 dB
-28 dB
-45 dB
-30-20-11
-9
302011
9
0
0 dB
The Meas Setup menu for the Spectrum Mask has the following controls:
IEEE802.11a/b/g Analysis
Spectrum Mask
Selects the spectrum mask specified in the IEEE802.11a/b standard.
(See Figure 3-3.)
DSSS (default)
OFDM
Figure 3-3: IEEE802.11a/b spectrum mask
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IEEE802.11a/b/g Analysis
The burst specified with Burst Select
is indicated with the green bar.
Overview
Measurement Setup for Transmit Power
The Meas Setup menu for the Transmit Power has the following controls:
Transmit Power
Burst Select
Selects the measurement: Transmit Power On or Down.
The measurement results for the selected item are displayed on the screen.
On. Selects the Transmit Power On measurement.
Down. Selects the Transmit Power Down measurement.
Specifies the index of a burst to display the measurement results.
Range: from (the number of all bursts in one acquisition block) −1 to 0.
0 (zero) indicates the latest burst.
The specified burst is indicated with the green bar in the Timing field on the
overview as shown in Figure 3-4.
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Figure 3-4: Burst indicator on the overview
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View Format
IEEE802.11a/b/g Analysis
This section provides information about the view formats of the IEEE802.11a/b/g
analysis. It consists of two parts:
View Format for Modulation Measurements
View Format for Power Measurements
Selecting View Content
You can change the view content with the View: Define key on the front panel. The
view contents depend on the measurement items as shown in Table 3-5.
In the EVM measurement, you can change the measurement content pressing
Power versus TimeConstellationVector / Constellation
EVM versus SCEVM
Power versus SCSC ConstellationVector / Constellation
Frequency ErrorOFDM FlatnessOFDM LinearityVector / Dot
Symbol Table-
Power analysis
Spectrum Mask--Transmit PowerWaveform (default)
Overview content
Waveform (default)
Spectrogram
Spectrogram
View: Define →
Subview content
Spectrum (default)
Constellation
EVM versus Time
Power versus Time
SC Constellation
EVM versus SC
Power versus SC
Frequency Error
OFDM Flatness
OFDM Linearity
Symbol Table
Spectrum (default)
Power On / Down
View Scale...
Measurement content
EVM
Mag Err
Phase Err
Mag Err
Phase Err
-
→
→
NOTE.
(Spectrum Analysis) mode. Refer to the RSA3408B User Manual.
RSA3408B Option 29 User Manual
The View Define menu for Spectrum Mask is the same as in the S/A
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Time (s)
• Vertical value: EVM (%)
Modulation type
The Select Subcarrier setting
in the Meas Setup menu
Subcarrier number setting
in the Meas Setup menu
(displayed when Select Subcarrier
is set to Single Subcarrier)
Preamble indicator: “Preamble On” is
displayed when one or more preambles are
enabled in Modulation Type Display Filter of
the Meas Setup menu.
Measurement readout
View Format for Modulation Measurements
EVM versus Time
The main view shows the EVM of carriers, or one or all subcarriers in a line graph,
as shown in Figure 3-5. The vertical axis represents EVM in percent and the
horizontal axis represents time in seconds.
Figure 3-5: EVM versus Time (main view)
3-12
The following table shows the measurement readout that is displayed on the left in
the main view:
Measurement readoutUnitDescription
Total Symbol-Total number of analysis symbols
EVM(rms)%, dBRMS value of EVM
(Peak)%, dBPeak value of EVM
(@Time)sThe peak time relative to the last data point
Mag Error(rms)%, dBRMS value of Mag Error
Phase Error (rms)
(Peak)%, dBPeak value of Mag Error
(@Time)sThe peak time relative to the last data point
degrees or
radiansRMS value of Phase Error
degrees or
(Peak)
(@Time)sThe peak time relative to the last data point
radiansPeak value of Phase Error
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IEEE802.11a/b/g Analysis
Scale Menu.
The Scale menu for EVM versus Time has the following controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically
to fit the waveform to the screen.
Horizontal Scale. Sets the range of the horizontal axis (time).
Horizontal Start. Sets the minimum value (left edge) of the horizontal axis.
NOTE.
The horizontal display range must be within the analysis range specified
using the Timing menu (refer to page 2-6).
Ver t ic al S c a l e . Sets the range of the vertical axis.
Refer to Table 3-6 for the setting range.
Vertical Start. When the measurement content is EVM, sets the minimum value
(bottom edge) of the vertical axis. Refer to Table 3-6 for the setting range.
Vertical Offset. When the measurement content is Mag Error or Phase Error, sets
the center value ((maximum + minimum) / 2) of the vertical axis.
Refer to Table 3-6 for the setting range.
Full Scale. Sets the scale of vertical axis to the default full-scale value.
Measurement Content... Selects how to display the vertical axis:
EVM. Represents the vertical axis with EVM (Error Vector Magnitude).
Mag Error. Represents the vertical axis with magnitude error.
Phase Error. Represents the vertical axis with phase error.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Time (s)
• Vertical value: Magnitude error (%)
Modulation type
The Select Subcarrier setting
in the Meas Setup menu
Subcarrier number setting
in the Meas Setup menu
(displayed when Select Subcarrier
is set to Single Subcarrier)
Measurement readout
Preamble indicator: “Preamble On” is
displayed when one or more preambles are
enabled in Modulation Type Display Filter of
the Meas Setup menu.
MagErr versus Time
The main view shows the magnitude error of carriers, or one or all subcarriers in a
line graph, as shown in Figure 3-6. The vertical axis represents magnitude error in
percent and the horizontal axis represents time in seconds.
Figure 3-6: MagErr versus Time (main view)
The measurement readout is the same as in EVM versus Time, shown in the table
on page 3-12.
Scale Menu.
Refer to the Scale menu of EVM versus Time on page 3-13.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Time (s)
• Vertical value: Phase error (degrees / radians)
Modulation type
The Select Subcarrier setting
in the Meas Setup menu
Subcarrier number setting
in the Meas Setup menu
(displayed when Select Subcarrier
is set to Single Subcarrier)
Measurement readout
Preamble indicator: “Preamble On” is
displayed when one or more preambles are
enabled in Modulation Type Display Filter of
the Meas Setup menu.
PhaseErr versus Time
The main view shows the Phase Error of carriers, or one or all subcarriers in a
line graph, as shown in Figure 3-7. The vertical axis represents phase error in
degrees or radians and the horizontal axis represents time in s.
Figure 3-7: PhaseErr versus Time (main view)
The measurement readout is the same as in EVM versus Time, shown in the table
on page 3-12.
Scale Menu.
Refer to the Scale menu of EVM versus Time on page 3-13.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Time (s)
• Vertical value: Power (dBm)
Modulation type
The Select Subcarrier setting
in the Meas Setup menu
Subcarrier number setting
in the Meas Setup menu
(displayed when Select Subcarrier
is set to Single Subcarrier)
Measurement readout
Preamble indicator: “Preamble On” is
displayed when one or more preambles are
enabled in Modulation Type Display Filter of
the Meas Setup menu.
Power versus Time
The main view shows the power of carriers, or one or all subcarriers in a line graph,
as shown in Figure 3-8. The vertical axis represents power in dBm and the
horizontal axis represents time in seconds.
Figure 3-8: Power versus Time (main view)
The following table shows the measurement readout that is displayed on the left in
the main view:
Measurement readoutUnitDescription
Total Symbol-Total number of analysis symbols
Power (rms)dBm, WRMS power of one or all subcarriers
(Peak)dBm, WPeak power of one or all subcarriers
(@Time)sThe peak time relative to the last data point
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IEEE802.11a/b/g Analysis
Scale Menu.
The Scale menu for Power versus Time has the following controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically
to fit the waveform to the screen.
Horizontal Scale. Sets the range of the horizontal axis (time).
Horizontal Start. Sets the minimum value (left edge) of the horizontal axis.
NOTE.
The horizontal display range must be within the analysis range specified
using the Timing menu (refer to page 2-6).
Ver t ic al S c a l e . Sets the range of the vertical axis.
Range: 50 μ to 50 dB.
Ver t ic al S t o p . Sets the maximum value (top edge) of the vertical axis.
Range: −50 to 50 dB.
Full Scale. Sets the scale of the vertical axis to the default full-scale value.
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IEEE802.11a/b/g Analysis
Marker readout
• Time (s)
• Magnitude
• Phase (degrees / radians)
Modulation type
The Select Subcarrier setting
in the Meas Setup menu
Subcarrier number setting
in the Meas Setup menu
(displayed when Select Subcarrier
is set to Single Subcarrier)
Measurement readout
Preamble indicator: “Preamble On” is
displayed when one or more preambles are
enabled in Modulation Type Display Filter of
the Meas Setup menu.
Constellation
The main view displays the constellation of one or all subcarriers in a rectangular
coordinates graph, as shown in Figure 3-9. The horizontal axis represents I and the
vertical axis represents Q.
Figure 3-9: Constellation (main view)
The measurement readout is the same as in EVM versus Time, shown in the table
on page 3-12.
Scale Menu.
The Scale menu for the constellation has the following controls:
Measurement Content... Selects vector or constellation display.
Vec tor. Selects vector display. A signal represented by phase and amplitude is
displayed in polar coordinate or IQ diagram. The red point indicates the
symbol position of the measured signal, and the yellow trace indicates the
locus of the signal between symbols.
Constellation. Selects constellation display. It is the same as the vector
display, except that only symbols of the measured signal are indicated in red,
and the locus between symbols is not shown. The cross marks indicate the
symbol positions of an ideal signal.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Subcarrier number
• Vertical value: EVM (%)
Modulation type
Symbol number setting
in the Meas Setup menu
Measurement readout
EVM versus SC
The displayed graph automatically toggles depending on the modulation format
(OFDM or Non-OFDM).
OFDM.
The bar graph in the main view shows the EVM of each subcarrier for one
analysis symbol specified using the Symbol # side key in the Meas Setup menu, as
shown in Figure 3-10. The vertical axis represents EVM in percent and the
horizontal axis represents subcarrier number ranging from − 32 to +31.
Figure 3-10: EVM versus SC (main view)
The following table shows the measurement readout that is displayed on the left in
the main view:
Measurement readoutUnitDescription
Total Symbol-Total number of analysis symbols
EVM(rms)%, dBRMS value of EVM
(Peak)%, dBPeak value of EVM
(@SC_No.)-The subcarrier number at the peak
Mag Error(rms)%, dBRMS value of Mag Error
(Peak)%, dBPeak value of Mag Error
(@SC_No.)-The subcarrier number at the peak
degrees or
Phase Error (rms)
(Peak)
(@SC_No.)-The subcarrier number at the peak
radiansRMS value of Phase Error
degrees or
radiansPeak value of Phase Error
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IEEE802.11a/b/g Analysis
Scale Menu.
The Scale menu in EVM versus SC for OFDM has the following
controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically
to fit the waveform to the screen.
Horizontal Scale. Sets the range of the horizontal axis (subcarrier number).
Range: 8 to 64.
Horizontal Start. Sets the minimum value (left edge) of the horizontal axis.
Range: −32 to 24.
Ver t ic al S c a l e . Sets the range of the vertical axis.
Refer to Table 3-7 for the setting range.
Vertical Start. When the measurement content is EVM, sets the minimum value
(bottom edge) of the vertical axis. Refer to Table 3-7 for the setting range.
Vertical Offset. When the measurement content is Mag Error or Phase Error, sets
the center value ((maximum + minimum) / 2) of the vertical axis. Refer to Table 3-7
for the setting range.
Full Scale. Sets the scale of vertical axis to the default full-scale value.
Measurement Content... Selects how to display the vertical axis:
EVM. Represents the vertical axis with EVM (Error Vector Magnitude).
Mag Error. Represents the vertical axis with magnitude error.
Phase Error. Represents the vertical axis with phase error.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Time (s)
• Vertical value: EVM (%)
Modulation type
Symbol number setting
in the Meas Setup menu
Measurement readout
Non-OFDM.
The main view displays the EVM of carriers by analysis symbol in a
bar graph, as shown in Figure 3-11. The vertical axis represents EVM in percent
and the horizontal axis represents time in s.
Figure 3-11: EVM versus Time (main view)
The measurement readout is the same as in EVM versus Time, shown in the table
on page 3-12.
Scale Menu.
The Scale menu in EVM versus SC for Non-OFDM has the same
controls as in EVM versus Time. Refer to page 3-13.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Subcarrier number
• Vertical value: Magnitude error (%)
Modulation type
Symbol number setting
in the Meas Setup menu
Measurement readout
MagErr versus SC
The displayed graph automatically toggles depending on the modulation format
(OFDM or Non-OFDM).
OFDM.
The bar graph in the main view shows the magnitude error of each
subcarrier for one analysis symbol specified using the Symbol # side key in the
Meas Setup menu, as shown in Figure 3-12.
The vertical axis represents magnitude error in percent and the horizontal axis
represents the subcarrier wave number ranging from −32 to +31.
Figure 3-12: MagErr versus SC (main view)
The measurement readout is the same as in EVM versus SC, shown in the table on
page 3-19.
Scale Menu.
Refer to the Scale menu of EVM versus SC on page 3-20.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Time (s)
• Vertical value: Magnitude error (%)
Modulation type
Symbol number setting
in the Meas Setup menu
Measurement readout
Non-OFDM.
The main view displays the magnitude error of carriers by analysis
symbol in a bar graph, as shown in Figure 3-13. The vertical axis represents the
magnitude error in percent and the horizontal axis represents time in seconds.
Figure 3-13: MagErr versus Time (main view)
The measurement readout is the same as in EVM versus Time, shown in the table
on page 3-12.
Scale Menu.
The Scale menu in MagErr versus SC for Non-OFDM has the same
controls as in EVM versus Time. Refer to page 3-13.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Subcarrier number
• Vertical value: Phase error (
degrees / radians
)
Modulation type
Symbol number setting
in the Meas Setup menu
Measurement readout
PhaseErr versus SC
The displayed graph automatically toggles depending on the modulation format
(OFDM or Non-OFDM).
OFDM.
The bar graph in the main view shows the phase error of each subcarrier for
one analysis symbol specified using the Symbol # side key in the Meas Setup
menu, as shown in Figure 3-14.
The vertical axis represents phase error in degrees or radians and the horizontal axis
represents the subcarrier wave number ranging from −32 to +31.
Figure 3-14: PhaseErr versus SC (main view)
The measurement readout is the same as in EVM versus SC, shown in the table on
page 3-19.
Scale Menu.
Refer to the Scale menu of EVM versus SC on page 3-20.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Time (s)
• Ver tical value: Phase error (degrees / radians)
Modulation type
Symbol number setting
in the Meas Setup menu
Measurement readout
Non-OFDM.
The main view displays the phase error of carriers by analysis symbol
in a bar graph, as shown in Figure 3-15. The vertical axis represents the phase error
in degrees or radians and the horizontal axis represents time in s.
Figure 3-15: PhaseErr versus Time (main view)
The measurement readout is the same as in EVM versus Time, shown in the table
on page 3-12.
Scale Menu.
The Scale menu in PhaseErr versus SC for Non-OFDM has the same
controls as in EVM versus Time. Refer to page 3-13.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Subcarrier number
• Vertical value: Power (dBm)
Modulation type
Symbol number setting
in the Meas Setup menu
Measurement readout
Power versus SC
The displayed graph automatically toggles depending on the modulation format
(OFDM or Non-OFDM).
OFDM.
The bar graph in the main view displays the power of each subcarrier for
one analysis symbol specified using the Symbol # side key in the Meas Setup
menu, as shown in Figure 3-16. The vertical axis represents power in dBm and the
horizontal axis represents the subcarrier number ranging from −32 to +31.
Figure 3-16: Power versus SC (main view)
The following table shows the measurement readout that is displayed on the left in
the main view:
Measurement readoutUnitDescription
Total Symbol-Total number of analysis symbols
Power (rms)dBm, WRMS power of all subcarriers
(Peak)dBm, WPeak power
(@SC_No.)-Subcarrier number at the peak
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IEEE802.11a/b/g Analysis
Scale Menu.
controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically
to fit the waveform to the screen.
Horizontal Scale. Sets the range of the horizontal axis (subcarrier number).
Range: 8 to 64.
Horizontal Start. Sets the minimum value (left edge) of the horizontal axis.
Range: −32 to 24.
Ver t ic al S c a l e . Sets the range of the vertical axis.
Range: 50 μ to 50 dB.
Ver t ic al S t o p . Sets the maximum value (top edge) of the vertical axis.
Range: −50 to 50 dBm.
Full Scale. Sets the scale of the vertical axis to the default full-scale value.
The Scale menu in Power versus SC for OFDM has the following
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Time (s)
• Vertical value: Power (dBm)
Modulation type
Symbol number setting
in the Meas Setup menu
Measurement readout
Non-OFDM.
The main view displays the power of carriers by analysis symbol in a
bar graph, as shown in Figure 3-17. The vertical axis represents power in dBm and
the horizontal axis represents time in seconds.
Figure 3-17: Power versus Time (main view)
The measurement readout is the same as in Power versus Time, shown in the table
on page 3-16.
Scale Menu.
The Scale menu in Power versus SC for Non-OFDM has the same
controls as in Power versus Time. Refer to page 3-17.
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IEEE802.11a/b/g Analysis
Marker readout
• Symbol number
• Magnitude
• Phase (degrees / radians)
Modulation type
Measurement readout
Symbol number setting
in the Meas Setup menu
SC Constellation
The displayed graph automatically toggles depending on the modulation format
(OFDM or Non-OFDM).
OFDM.
The main view displays the constellation of subcarriers in a
rectangular coordinate graph for an analysis symbol, as shown in Figure 3-18.
The horizontal axis represents I and the vertical axis represents Q.
Figure 3-18: Symbol Constellation (main view)
The measurement readout is the same as in EVM versus SC, shown in the table on
page 3-19.
Scale Menu.
Same as in Constellation. Refer to page 3-18.
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IEEE802.11a/b/g Analysis
Marker readout
• Symbol number
• Magnitude
• Phase (degrees / radians)
Modulation type
Measurement readout
Symbol number setting
in the Meas Setup menu
Non-OFDM.
The main view displays the constellation of carriers in a
rectangular coordinate graph for an analysis symbol, as shown in Figure 3-19.
The horizontal axis represents I, and the vertical axis represents Q.
Figure 3-19: Symbol Constellation (main view)
The measurement readout is the same as in EVM versus Time, shown in the table
on page 3-12.
Scale Menu.
Same as in Constellation. Refer to page 3-18.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Time (s)
• Vertical value: Frequency error (Hz)
Modulation type
Measurement readout
Frequency Error
The main view displays the center frequency deviation over time in a line graph, as
shown in Figure 3-20. The vertical axis represents frequency error in kHz, and the
horizontal axis represents time in seconds.
Figure 3-20: Frequency error (main view)
The following table shows the measurement readout that is displayed on the left in
the main view:
Measurement readoutUnitDescription
Total Symbol-Total number of analysis symbols
Center Frequency Error (rms)kHzRMS frequency error
(Peak)kHzPeak frequency error
(@Time)sThe peak time relative to the last data point
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IEEE802.11a/b/g Analysis
Scale Menu.
The Scale menu for Frequency Error has the following controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically
to fit the waveform to the screen.
Horizontal Scale. Sets the range of the horizontal axis (time).
Horizontal Start. Sets the minimum value (left edge) of the horizontal axis.
NOTE.
The horizontal display range must be within the analysis range specified
using the Timing menu (refer to page 2-6).
Ver t ic al S c a l e . Sets the range of the vertical axis (frequency).
Range: 500 m to 500 kHz.
Ver t ic al O f f s e t. Sets the maximum value (top edge) of the vertical axis.
Range: −500 k to 500 kHz.
Full Scale. Sets the scale of the vertical axis to the default full-scale value.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Subcarrier number
• Vertical value: Power (dBm)
Measurement readout
OFDM Flatness
The main view displays each subcarrier wave flatness in a bar graph, as shown in
Figure 3-21. The vertical axis represents the deviation power of average energy
in dB, and the horizontal axis represents subcarrier wave number ranging from
−32 to +31.
Figure 3-21: OFDM flatness (main view)
Verify that the measurement results of the bar graph fall within the threshold level
displayed with two red lines.
The following table shows the measurement readout that is displayed on the left in
the main view:
Measurement readoutUnitDescription
Total Symbol-Total number of analysis symbols
Center Frequency LeakagedBCarrier leakage power (<2 dB in IEEE802.11a standard)
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IEEE802.11a/b/g Analysis
Scale Menu.
Aut o Scale. Sets the start value and the scale of the vertical axis automatically
to fit the waveform to the screen.
Horizontal Scale. Sets the range of the horizontal axis (subcarrier number).
Range: 8 to 64.
Horizontal Start. Sets the minimum value (left edge) of the horizontal axis.
Range: −32 to 24.
Ver t ic al S c a l e . Sets the range of the vertical axis.
Range: 100 μ to 100 dB.
Ver t ic al S t o p . Sets the maximum value (top edge) of the vertical axis.
Range: −150 to 50 dB.
Full Scale. Sets the scale of the vertical axis to the default full-scale value.
The Scale menu for OFDM Flatness has the following controls:
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IEEE802.11a/b/g Analysis
Marker readout
• Marker position (set with Marker Setup → Marker X Position)
• Horizontal value: Reference power (mW)
• Vertical value: Measurement power (mW)
Measurement readout
The blue line represents the ideal line.
OFDM Linearity
The main view displays the linearity of OFDM modulation in a line graph, as
shown in Figure 3-22. The vertical axis represents actual measurement values
in mW, and the horizontal axis represents the ideal values in mW.
Figure 3-22: OFDM linearity (main view)
The measurement readout shows only the total number of analysis symbols.
Scale Menu.
The Scale menu for OFDM Linearity has the following controls:
Measurement Content... Selects vector or dot display.
Vec tor. Displays yellow lines between the dots (default).
Dot. Displays the calculated result as a series of red dots.
The measurement results are displayed with the horizontal and vertical axes scaled
automatically to fit the graph to the screen.
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IEEE802.11a/b/g Analysis
Marker readout
• Symbol number
• Symbol value
Measurement readout
Symbol Table
The main view displays the symbol table, as shown in Figure 3-23.
The table can be displayed with binary, octal, or hexadecimal digits.
Figure 3-23: Symbol table (main view)
The measurement readout shows only the total number of analysis symbols.
Scale Menu.
The Scale menu for Symbol Table has the following controls:
Radix. Selects the radix for displaying the table:
Hex. Hexadecimal digit
Oct. Octal digit
Bin. Default. Binary digit
Hex and Oct indicate values of binary data string in units of modulation symbol.
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View Format for Power Measurement
Marker readout
• Frequency (Hz)
• Power (dBm)
This subsection describes all view formats for power analysis.
IEEE802.11a/b/g Analysis
Spectrum Mask
The spectrum mask measurement verifies that the base station is not transmitting
excessive power outside of its designated channel.
OFDM.
shown in Figure 3-24. The vertical axis represents power in dBm and the
horizontal axis represents frequency in Hz.
The screen displays the spectrum waveform and mask in a line graph, as
Figure 3-24: Spectrum mask (OFDM)
Verify that the measurement results (line graph) fall within the threshold level.
This view does not display the measurement readouts.
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IEEE802.11a/b/g Analysis
Scale Menu.
controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically
to fit the waveform to the screen.
Horizontal Scale. Sets the scale of the horizontal axis (frequency).
Horizontal Start. Sets the minimum value (left edge) of the horizontal axis.
Ver t ic al S c a l e . Sets the scale of the vertical axis (power).
Range: 100 μ to 100 dB.
Ver t ic al S t o p . Sets the maximum value (top edge) of the vertical axis.
Range: −100 to 100 dBm.
Full Scale. Sets the scale of the vertical axis to the default full-scale value.
The Scale menu in Spectrum Mask for OFDM has the following
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IEEE802.11a/b/g Analysis
Marker readout
• Frequency (Hz)
• Power (dBm)
Non-OFDM.
The screen displays the spectrum waveform and mask in a line graph,
as shown in Figure 3-25. The vertical axis represents power in dBm and the
horizontal axis represents frequency in Hz.
Figure 3-25: Spectrum mask (DSSS)
Verify that the measurement results of the line graph fall within the threshold level.
This view does not display the measurement readouts.
Scale Menu.
The Scale menu in Spectrum Mask for Non-OFDM has the same
controls as for OFDM. Refer to page 3-38.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Time (μs)
• Vertical value: Power (mW)
Measurement readout
Transmit Power
Displays the transmit power on/down ramp in a line graph with the standard mask.
NOTE.
On.
The transmit power measurement handles non-OFDM signals.
The main view displays the transmit power-on ramp in a line graph.
The vertical axis represents power in watts and the horizontal axis represents time
in seconds.
Figure 3-26: Transmit power on (main view)
Verify that the measurement results (line graph) fall within the threshold level.
The following table shows the measurement readout that is displayed on the left in
the main view:
Measurement readoutUnitDescription
Power OnsTransmit power-on ramp from 10 to 90%
Power DownsTransmit power-down ramp from 90 to 10%
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IEEE802.11a/b/g Analysis
Transmit
power
output
01234Time (
μ
s)
Max Tx power
90% max
10% max
Figure 3-27 shows the IEEE802.11b standard for the transmit power-on ramp.
Figure 3-27: IEEE802.11b Transmit power-on ramp
Scale Menu.
The Scale menu for Transmit Power On has the following controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically
to fit the waveform to the screen.
Horizontal Scale. Sets the range of the horizontal axis (time).
Horizontal Start. Sets the minimum value (left edge) of the horizontal axis.
NOTE.
The horizontal display range must be within the analysis range specified
using the Timing menu (refer to page 2-6).
Ver t ic al S c a l e . Sets the range of the vertical axis (power).
Range: 800 p to 800 μW.
Ver t ic al S t o p . Sets the maximum value (top edge) of the vertical axis.
Range: 0 to 1.6 mW.
Full Scale. Sets the scale of the vertical axis to the default full-scale value.
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IEEE802.11a/b/g Analysis
Marker readout
• Horizontal value: Time (μs)
• Vertical value: Power (mW)
Measurement readout
Transmit
power
output
01234 Time (
μ
s)
Max Tx power
90% max
10% max
Down.
The main view displays the transmit power-down ramp in a line graph. The
vertical axis represents power in watts and the horizontal axis represents time
in seconds.
Figure 3-28: Transmit power down (main view)
Verify that the measurement results (line graph) fall within the threshold level.
The readout is the same as Transmit Power-On. Refer to page 3-40.
Figure 3-29 shows the IEEE802.11b standard for the transmit power-down ramp.
Figure 3-29: IEEE802.11b Transmit power-down ramp
Scale Menu.
The Scale menu for Transmit Power Down has the same controls as
for Transmit Power On. Refer to page 3-41.
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802.11n (nx1) Analysis
Standard...802.11n (nx1)
Mode
S/A
Demod
Time
Measure menu items
Modulation measurement
Transfer Function (Amp)
Transfer Function (Phase)
Delay Profile
EVM versus Time
Power ver sus T ime
Constellation
EVM versus SC
Power ver sus S C
SC Constellation
Frequency Error
OFDM Flatness
OFDM Linearity
Symbol Table
Power measurement
Spectrum Mask
SISO (1x1) only
This section describes the basic operation of the IEEE802.11n (nx1, Multi-Input
Single-Output) analysis. You can access the measurement items by pressing
Demod→ Standard... → 802.11n (nx1) as shown in Figure 3-30.
NOTE.
The 802.11n (nx1) analysis includes the 1x1 (SISO: Single-Input
Single-Output) and the 2x1 (MISO: Multi-Input Single-Output) measurements.
The measurements other than Transfer Function and Delay Profile are for
SISO only.
Figure 3-30: IEEE
While SISO is a traditional one-to-one communication method, MISO is a
RSA3408B Option 29 User Manual
many-to-one system for improving the communication speed. The next section
explains how the analyzer processes data in MISO (2x1).
802.11
n (nx1) measurement menu
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802.11n (nx1) Analysis
Transfer Functions (TF) calculation
LT F
LT FData 1LT FData 2
Tx Antenna 1Tx Antenna 2
Tx1 PacketTx2 Packet
Rx Antenna
Acquired packets
Processed in the analyzer
Measurement and display
• Transfer function (Amplitude / Phase)
• Delay profile
* Abbr.
LTF: Long Training Field.
TFm: Transfer Function from Tx antenna m to Rx antenna.
RSA3408B
TF1
TF2
Data Process Flow for MISO (2x1)
Figure 3-31 shows the data process flow in MISO (2x1). Packet 1 and 2 transmitted
from Tx antenna 1 and 2 respectively are received by an Rx antenna. Packet 1 and 2
acquired by the analyzer are processed to extract LTF (Long Training Field). Then,
the transfer function is calculated using the LTF parts. For MISO (2x1), two
transfer functions are obtained according to the combination of the Tx and Rx
antennas so the delay profile as well as the amplitude and phase transfer functions
can be observed on the screen.
Figure 3-31: Data process flow for MISO (2x1)
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Basic Measurement Procedure
The basic measurement procedures are described for the modulation analysis and
the power analysis.
802.11n (nx1) Analysis
Modulation Measurement
Do the following steps to perform the modulation measurement.
1. Press Demod → Standard... → 802.11n (nx1).
2. Set frequency and span appropriately using the Frequency/Channel and the
Span keys. Refer to Setting Frequency and Span on page 2-3.
3. Set the amplitude appropriately using the Amplitude key.
NOTE.
will be displayed in the red box at the center top of the screen. In this case, raise
the reference level.
4. Press the Acquisition/Analysis key and set the acquisition and analysis
5. After acquiring measurement data, stop the data acquisition using the
6. Press the Measure key and select a measurement item.
7. Press Meas Setup to set the measurement parameters.
If the input signal level is too high, “Overrange - increase RefLev or Atten"
parameters. Refer to Setting Acquisition and Analysis Parameters on page 2-6.
Run/Stop key.
For example, press the Transfer Function (Amp) side key to observe the
amplitude transfer function.
For details on setting the Measurement Setup menu, refer to page 3-47.
8. Press Meas Setup → Analyze to start the analysis for the acquired data with
9. Use the View menu to modify the displayed graph.
RSA3408B Option 29 User Manual
the specified parameters.
If you cancel the analysis, press the Cancel-Back (top) side key.
For details on setting the views, refer to View Format on page 3-55.
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802.11n (nx1) Analysis
Power Measurement
Meas Setup Menu
The power analysis includes only the Spectrum Mask measurement.
Do the following steps to perform the measurement.
1. Press Demod → Standard... → 802.11n (nx1).
2. Set frequency and span appropriately using the Frequency/Channel and the
Span keys. Refer to Setting Frequency and Span on page 2-3.
3. Set the amplitude appropriately using the Amplitude key.
NOTE.
If the input signal level is too high, “Overrange - increase RefLev or Atten"
will be displayed in the red box at the center top of the screen. In this case, raise
the reference level.
4. Press Measure → Spectrum Mask to observe the spectrum mask.
5. Press the Meas Setup key and set the measurement parameters.
For details on setting the Measurement Setup menu, refer to page 3-52.
6. Use the View menu to modify the displayed graph.
For details on setting the views, refer to View Format on page 3-55.
Press the Meas Setup key to set the measurement parameters. The Meas Setup
menu varies among the measurement items. Refer to the section shown in
Tab le 3-8 .
Table 3-8: Measurement setup reference for the 802.11n (nx1) analysis
Measurement itemReference section
Modulation measurements
Transfer Function
Delay Profile
EVM versus Time
Power versus Time
Constellation
EVM versus SC
Power versus SC
SC Constellation
Frequency Error
OFDM Flatness
OFDM Linearity
Symbol Table
Power measurements
Spectrum MaskMeasurement Setup for Spectrum Mask on page 3-52
* SC: Subcarrier
Measurement Setup for Modulation Measurements
on page 3-47
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Measurement Setup for Modulation Measurements
The Meas Setup menu for the modulation analysis has the following controls:
802.11n (nx1) Analysis
Analyze
Analysis Parameter...
Performs measurements for packets in the analysis range.
NOTE.
When you change settings in the Meas Setup menu described below, press
the Analyze side key to perform the measurement for the modified settings.
You need to set the analysis parameters before pressing the Analyze side key.
Synchronization.
LT F. Default. Synchronizes with the Long Training Field.
Pilot. Synchronizes with the pilot signals.
Equalization.
Selects the synchronization method.
Determines whether to apply the data correction using the
long training symbol during the analysis.
On. Default. Enables the data correction.
Off. Disables the data correction.
Signal Format.
1x1. Default. Selects the communication by one Tx and one Rx antenna.
Selects the signal format.
2x1. Selects the communication by two Tx antennas and one Rx antenna.
Select Tx Antenna...
For Transfogram (Amplitude/Phase) or Delayogram in the subview only.
Selects the transmission antenna. This item is available when the analysis is done
with Signal Format set to 2x1.
Tx Antenna 1. Displays the measurement results for signals transmitted by
Tx Antenna 2. Displays the measurement results for signals transmitted by
Packet #
Selects a packet to analyze.
Range: −[(the number of packets in the analysis range) − 1] to 0.
Zero (0) represents the latest packet.
RSA3408B Option 29 User Manual
Tx Antenna 1.
Tx Antenna 2.
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802.11n (nx1) Analysis
Select Subcarrier...
Subcarrier #
Symbol #
Selects the subcarrier type for displaying the graph.
Data + Pilot. Default. Displays the measurement results for data and pilot.
Data. Displays the measurement results for data only.
Pilot. Displays the measurement results for pilot only.
Single Subcarrier. Displays the measurement results for the subcarrier
specified using the Subcarrier # side key below.
Specifies the subcarrier number for the measurement. Range: −64 to +63.
The function varies by measurement as shown in Table 3-9.
Specifies the analysis symbol number for the measurement.
The function varies by measurement as shown in Table 3-9.
Range: −[(the number of symbols in the analysis range) − 1] to 0.
Zero (0) represents the latest analysis symbol.
NOTE.
For definition of the analysis symbol, refer to page 3-50.
The Packet #, Select Subcarrier..., Subcarrier #, and Symbol # menu items have
different effect by measurement as shown in Table 3-9.
Table 3-9: Submenu availability
Select
Measure menu itemPacket #
Transfer Function D - M D
Delay Profile D - - D
EVM versus Time M D S M
Power versus Time M D S M
Constellation M D S M
EVM versus SC D - M D
Power versus SC D - M D
SC Constellation D - M D
Frequency Error M D S M
OFDM Flatness - - M OFDM Linearity - - - Symbol Table D - M D
D: Changing the setting updates the measurement data.
M: Changing the setting updates the marker position.
S: Changing the setting updates the measurement data only when
Select Subcarrier is set to Single Subcarrier.
Abbreviation. SC: Subcarrier
Subcarrier...Subcarrier #Symbol #
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802.11n (nx1) Analysis
Definition of the Analysis Symbol.
In the modulation analysis, it is important to
calculate average values of RMS voltage or center frequency error for enough time
to get good analysis results. The length of a signal to calculate the RMS voltage or
center frequency error is called “analysis symbol” in the WLAN analysis software.
For example, frequency error by the analysis symbol is displayed on the center
frequency error view. Although “symbol” is defined for OFDM in the 802.11n
standard, “analysis symbol” is used in the WLAN analysis software taking the
other modulation types into account.
The following views display the averaged values by analysis symbol for power,
EVM, magnitude error, and phase error, respectively.
Power versus Time
EVM versus Time
MagErr versus Time
PhaseErr versus Time
The following views display analysis results of power, EVM, magnitude error, and
phase error, respectively for each data point, chip, or subcarrier contained in one
analysis symbol.
Power versus SC
EVM versus SC
MagErr versus SC
PhaseErr versus SC
The length of an analysis symbol depends on the modulation type as follows:
Table 3-10: Length of an analysis symbol, IEEE802.11n
Part of a signalType of the signalLength of an analysis symbol
Data partOFDM80 (20 MHz) / 160 (40 MHz)
sample points
DSSS88 chips
CCK80 chips
PBCC80 data points
sample points
Long OFDM training field160 (20 MHz) / 320 (40 MHz)
sample points
PLCP preamble1584 chips
Short PLCP preamble792 chips
PLCP header528 chips
Short PLCP header264 chips
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802.11n (nx1) Analysis
GI
(Guard Interval)
Preamble
Data
PLCP Packet
format
Operation of PHY
(Physical Layer)
Select an item and
turn it on or off.
Standard
Modulation Type
Display Filter...
Selects the modulation type(s) to display the measurement results on the screen.
The results and graph are shown only for the types set to On. See Figure 3-32.
Select cell to edit.
Selects an item to change the on/off setting in the table on screen.
The table consists of five blocks as shown in Figure 3-32. The selected item appears
on the second side key where you can turn on or off.
11bg. Turns on or off the 802.11b and g formats.
All PLCP Packet format On/Off.
Turns on or off all of the following PLCP (Physical
Layer Convergence Protocol) packet formats.
Legacy. Packets are transmitted in the legacy 802.11a/g format.
Mixed Mode. Packets are transmitted with a preamble compatible with the
legacy 802.11a/g. The rest of the packet has a new format.
Green Field. High throughput packets are transmitted without a
legacy compatible part.
All Preambles On/Off.
Signal (HT-SIG)
Turns on or off all of the following preambles.
Short Training Field (HT-STF)
Long Training Field (HT-LTF)
Figure 3-32: Modulation Type Display Filter setting in the nx1 analysis
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802.11n (nx1) Analysis
All Data On/Off.
OFDM 64QAM
OFDM 16QAM
OFDM QPSK
OFDM BPSK
All GI On/Off.
Normal (800 ns)
Short (400 ns)
All Operation of PHY On/Off.
Turns on or off all of the following data.
Turns on or off all of the following GI (Guard Interval).
Turns on or off all of the following operations of PHY
Duplicate. Duplicate Legacy Mode in which the device operates in a 40 MHz
channel composed of two adjacent 20 MHz channels.
Upper. 40 MHz Upper Mode used to transmit a legacy or HT packet in the
upper 20 MHz channel of a 40 MHz channel.
Lower. 40 MHz Lower Mode used to transmit a legacy or HT packet in the
lower 20 MHz channel of a 40 MHz channel.
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802.11n (nx1) Analysis
Power spectral density
Transmit spectrum mask
Typical signal spectrum
Frequency (MHz)
−
20 dB
−
28 dB
−
45 dB
−
30
−
20
−
11
−
9
302011
9
0
20 MHz
40 MHz
0 dB
Frequency (MHz)
−
60
−
40
−
21
−
19
604021
19
0
−
20 dB
−
28 dB
−
45 dB
0 dB
Power spectral density
Transmit spectrum mask
Typical signal spectrum
Span = 100 MHz
Span = 150 MHz
Measurement Setup for Spectrum Mask
The Meas Setup menu for the Spectrum Mask has the following controls:
Spectrum Mask
Selects the transmit spectral mask specified in the IEEE802.11n standard.
(See Figure 3-33.)
20MHz. Default. Selects the mask for 20 MHz transmission.
40MHz. Selects the mask for 40 MHz transmission.
Figure 3-33: 802.11n (nx1) spectrum mask
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802.11n (nx1) Analysis
Lower side Upper side
A
B
C
D
A
D
C
B
Limits...
You can edit the spectral mask. Modify the offset frequency and limit level for the
points A to D shown in Figure 3-34. The setting values are indicated for each point
in the limits table on the bottom of the screen. Use the following controls:
Select column to edit.
Lower Offset Frequency.
Selects the column (A to D) to edit in the limits table.
Sets the frequency offset from the center frequency for the
Sets the limit level for the selected point in the upper side.
Range: −200 to 200 dBr.
Figure 3-34: Editing the spectral mask
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802.11n (nx1) Analysis
Symmetric Mask.
On. Creates a symmetrical mask. Set the frequency offset and limit values for
Determines whether the mask is symmetrical or not.
the lower side only.
Off. Allows you to set the frequency offset and limit values for the lower and
the upper side separately.
Default Limits.
Returns the offset and limit settings to the default values.
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View Format
802.11n (nx1) Analysis
This section provides information about the view formats specific to the 802.11n
(nx1) analysis. It consists of two parts:
View Format for Modulation Measurements
View Format for Power Measurements
Selecting View Content
You can change the view content with the View: Define key on the front panel.
The view contents depend on the measurement items as shown in Table 3-11.
In the EVM measurement, you can change the measurement content pressing
View: Scale/Lines → View Scale....
Table 3-11: View content selection, 802.11n (nx1)
View: Scale/Lines
→
View: Define
Measurement item
Modulation measurement
Transfer Function (Amplitude)
Transfer Function (Phase)Delay ProfileEVM versus TimeEVM
Power versus TimeConstellationVector / Constellation
EVM versus SCEVM
Power versus SCSC ConstellationVector / Constellation
Frequency ErrorOFDM FlatnessOFDM LinearityVector / Dot
Symbol Table-
Power measurement
Spectrum Mask---
* SC: Subcarrier
Overview content
Waveform (default)
Spectrogram
View: Define →
Subview content
Spectrum (default)
Transogram (Amplitude / Phase)
Transfer Function (Amplitude / Phase)
Delayogram
Delay Profile
Constellation
EVM versus Time
Power versus Time
SC Constellation
EVM versus SC
Power versus SC
Frequency Error
OFDM Flatness
OFDM Linearity
Symbol Table
View Scale...
Measurement content
-
Mag Err
Phase Err
Mag Err
Phase Err
→
→
NOTE.
(Spectrum Analysis) mode. Refer to the RSA3408B User Manual.
RSA3408B Option 29 User Manual
The View menu for Spectrum Mask is the same as in the S/A
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802.11n (nx1) Analysis
List Display
The measurement results are represented in graph form by default. You can select
the list display as shown in Figure 3-35. Press View: Define → Display → List.
Figure 3-35: List display
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View Format for Modulation Measurements
Packet information
(common to all modulation
measurements)
Measured values
(vary by measurements)
Measurement graph
The modulation measurement result is displayed in the main view, showing the
packet information and measured values on the left side and the measurement
graph on the right side (see Figure 3-36).
Figure 3-36: Measurement result display (an example of EVM versus Time)
802.11n (nx1) Analysis
Packet Information
The packet information displayed on the left side of the main view is common to
all modulation measurements, containing the following fields:
Format.
Legacy. Packets are transmitted in the legacy 802.11a/b/g format.
Mixed Mode. Packets are transmitted with a preamble compatible with the
indicates the signal format.
legacy 802.11a/g and the rest of the packet has a new format.
Green Field. HT packets are transmitted without a legacy 802.11a/b/g
compatible part.
Mode.
Indicates the operating mode. There are two major modes:
Legacy. The legacy mode equivalent to 802.11a/b/g.
HT. The HT (High Throughput) mode specified in 802.11n.
Each mode is further divided to the following modes by the frequency band used:
20 MHz. Uses 20 MHz bandwidth.
40 MHz. Uses 40 MHz bandwidth (HT mode only).
RSA3408B Option 29 User Manual
Duplicate. Uses a 40 MHz channel composed of two adjacent 20 MHz
channel.
Upper. Uses the upper 20 MHz channel of a 40 MHz channel.
Lower. Uses the lower 20 MHz channel of a 40 MHz channel.
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802.11n (nx1) Analysis
Symbol.
Long or Short Preamble
L-STF (Legacy Short Training Field)
L-LTF (Legacy Long Training Field)
Long or Short Header
L-SIG (Legacy Signal Field)
DSSS 1M or 2M
CCK 5.5M or 11M
PBCC 5.5M, 11M, 22M, or 33M
OFDM BPSK, QPSK, 16QAM, or 64QAM
HT-STF (High Throughput Short Training Field)
HT-LTF (High Throughput Long Training Field)
HT-SIG (High Throughput Signal Field)
SMap.
DM (Direct Mapping)
Indicates the type of preamble, header, or data of the analysis symbol.
Indicates the spatial mapping.
STBC (Space Time Block Coding)
GI.
Indicates the guard interval.
Normal (800 ns)
Short (400 ns)
MCS.
Indicates the MCS (Modulation and Coding Scheme) index (0 to 76)
specified in 802.11n. For the details on MCS, refer to the 802.11n specification.
Total Packet / Symbol.
Indicates the total number of packets and analysis symbols
in the analysis range, respectively.
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802.11n (nx1) Analysis
Marker readout
• Horizontal value: Subcarrier number
• Vertical value: Amplitude variation (dBm)
Transmitting and receiving antennas
for Trace 1 (yellow) and Trace2 (green)
(Displayed when selecting 2x1 in Meas Setup
→
Analysis Parameter → Signal Format)
Packet information
(refer to page 3-57)
Transfer Function
(Amplitude)
The main view displays the amplitude transfer function as shown in Figure 3-37.
This graph indicates an amplitude variation for each subcarrier during the signal
propagation from Tx system to Rx system. The horizontal axis represents
subcarrier number and the vertical axis represents amplitude variation in dBm.
Figure 3-37: Transfer function, amplitude (main view)
Scale Menu.
The Scale menu for Transfer Function (Amplitude) has the following
controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically
to fit the waveform to the screen.
Horizontal Scale. Sets the range of the horizontal axis.
Range: 16 to 128 subcarriers.
Horizontal Start. Sets the minimum value (left edge) of the horizontal axis.
Range: −64 to 8.
Ver t ic al S c a l e . Sets the range of the vertical axis.
Range: 100 μ to 100 dB.
Vertical Start. Sets the minimum value (bottom edge) of the vertical axis.
Range: −200 to 0 dBm.
Full Scale. Sets the scale of the vertical axis to the default full-scale value.
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802.11n (nx1) Analysis
Marker readout
• Horizontal value: Subcarrier number
• Color value: Amplitude (dBm)
• Vertical value: Time (packet number)
Transmitting and receiving antennas.
Transmitting antenna can be selected by
Meas Setup → Select Tx Antenna...
Transfogram (Amplitude)
Subview only. It displays the time series of amplitude transfer function.
The amplitude at a given subcarrier and time (packet number) is displayed as a
color map in a two dimensional diagram as shown in Figure 3-38.
Figure 3-38: Transogram, amplitude (subview)
Scale Menu.
The Scale menu for Transogram (Amplitude) has the following
controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically to
fit the waveform to the screen.
Horizontal Scale. Sets the scale of the horizontal axis.
Range: 16 to 128 subcarriers.
Horizontal Start. Sets the start subcarrier number of the horizontal axis.
Range: −64 to 8.
Ver t ic al S i z e. Sets the full scale of the vertical axis.
Range: 58 to 59392 packets.
Vertical Start. Sets the start packet number of the vertical axis.
Range: − [(the number of packets in the analysis range) − 1] to 0.
Zero (0) represents the latest packet.
Color Scale. Sets the range of the color axis.
Range: 10 to 100 dB in a 1-2-5 sequence.
The transfogram is displayed in 100 steps (100 colors) from the minimum value
(blue) to the maximum value (red) in the default state.
Color Stop. Sets the maximum value (top edge) of the color axis.
Range: −100 to 100 [dB].
Full Scale. Sets Color Stop to 0 (zero) and Color Scale to 100 dBm.
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802.11n (nx1) Analysis
Marker readout
• Horizontal value: Subcarrier number
• Vertical value: Phase lead/lag (degrees)
Transmitting and receiving antennas
for Trace 1 (yellow) and Trace2 (green)
(Displayed when selecting 2x1 in Meas Setup
→
Analysis Parameter → Signal Format)
Packet information
(refer to page 3-57)
Transfer Function
(Phase)
The main view displays the phase transfer function as shown in Figure 3-39. This
graph indicates a phase lead or lag for each subcarrier during the signal propagation
from Tx system to Rx system. The horizontal axis represents subcarrier number
and the vertical axis represents phase lead or lag in degrees or radians.
Figure 3-39: Transfer function, phase (main view)
Scale Menu.
The Scale menu for Transfer Function (Amplitude) has the following
controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically
to fit the waveform to the screen.
Horizontal Scale. Sets the range of the horizontal axis.
Range: 16 to 128 subcarriers.
Horizontal Start. Sets the minimum value (left edge) of the horizontal axis.
Range: −64 to 8.
Ver t ic al S c a l e . Sets the range of the vertical axis.
Range: 800 μ to 800 degrees.
Ver t ic al S t a r. Sets the minimum value (bottom edge) of the vertical axis.
Range: −1200 to 400 degrees.
Full Scale. Sets the scale of the vertical axis to the default full-scale value.
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802.11n (nx1) Analysis
Transmitting and receiving antennas.
Transmitting antenna can be selected by
Meas Setup → Select Tx Antenna...
Marker readout
• Horizontal value: Subcarrier number
• Color value: Phase (degrees)
• Vertical value: Time (packet number)
Transfogram (Phase)
Subview only. It displays the time series of phase transfer function.
The phase at a given subcarrier and time (packet number) is displayed as a
color map in a two dimensional diagram as shown in Figure 3-40.
Figure 3-40: Transfogram, phase (subview)
Scale Menu.
The Scale menu for Transogram (Phase) has the following controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically to
fit the waveform to the screen.
Horizontal Scale. Sets the scale of the horizontal axis.
Range: 16 to 128 subcarriers.
Horizontal Start. Sets the start channel number of the horizontal axis.
Range: −64 to 8.
Ver t ic al S i z e. Sets the full scale of the vertical axis.
Range: 58 to 59392 packets.
Vertical Start. Sets the start packet number of the vertical axis.
Range: − [(the number of packets in the analysis range) − 1] to 0.
Zero (0) represents the latest packet.
Color Scale. Sets the range of the color axis:
Range: 10 to 100 dB in 1-2-5 sequence.
The transogram is displayed in 100 steps (100 colors) from the minimum value
(blue) to the maximum value (red) in the default state.
Color Stop. Sets the maximum value (top edge) of the color axis.
Range: −100 to +100 dB.
Full Scale. Sets Color Stop to 0 (zero) and Color Scale to 100 dBm.
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802.11n (nx1) Analysis
Marker readout
• Horizontal value: Delay time (s)
• Vertical value: Amplitude (dBm)
Transmitting and receiving antennas
for Trace 1 (yellow) and Trace2 (green)
(Displayed when selecting 2x1 in Meas Setup
→
Analysis Parameter → Signal Format)
Packet information
(refer to page 3-57)
Delay Profile
The main view shows the delay profile as shown in Figure 3-41. In the n× 1
communication method, transmitted signals propagate through multipath with
different distance to reach a receiving antenna. The path difference causes the
received signals some temporal dispersion. The delay profile shows the power
distribution to the delay time. The vertical axis represents amplitude in dBm and
the horizontal axis represents delay time in seconds.
Figure 3-41: Delay profile (main view)
Scale Menu.
The Scale menu for Delay Profile has the following controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically
to fit the waveform to the screen.
Horizontal Scale. Sets the range of the horizontal axis.
Range: S
/16 to S0 (sec) where S0 is the initial horizontal scale.
0
Horizontal Start. Sets the minimum value (left edge) of the horizontal axis.
Range: −S
/2 to [S0/2 − (Horizontal Scale)] (sec).
0
Ver t ic al S c a l e . Sets the range of the vertical axis.
Range: 100 μ to 100 dB.
Ver t ic al S t a r. Sets the minimum value (bottom edge) of the vertical axis.
Range: −200 to 0 dBm.
Full Scale. Sets the scale of the vertical axis to the default full-scale value.
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802.11n (nx1) Analysis
Marker readout
• Horizontal value: Delay time (s)
• Color value: Amplitude (dBm)
• Vertical value: Time, packet number
Transmitting and receiving antennas.
Transmitting antenna can be selected by
Meas Setup → Select Tx Antenna...
Delayogram
Subview only. It displays the time series of delay profile.
The power at a given delay time and packet number is displayed as a color map in
a two dimensional diagram as shown in Figure 3-42.
Figure 3-42: Delayogram (subview)
Scale Menu.
The Scale menu for Delayogram has the following controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically to
fit the waveform to the screen.
Horizontal Scale. Sets the range of the horizontal axis.
Range: S
/16 to S0 (sec) where S0 is the initial horizontal scale.
0
Horizontal Start. Sets the minimum value (left edge) of the horizontal axis.
Range: −S
/2 to [S0/2 − (Horizontal Scale)] (sec).
0
Ver t ic al S i z e. Sets the full scale of the vertical axis in frames.
Range: 58 to 59392.
Vertical Start. Sets the start packet number of the vertical axis.
Range: − [(the number of packets in the analysis range) − 1] to 0.
Zero (0) represents the latest packet.
Color Scale. Sets the range of the color axis:
Range: 10 to 100 dB in 1-2-5 sequence.
The delayogram is displayed in 100 steps (100 colors) from the minimum value
(blue) to the maximum value (red) in the default state.
Color Stop. Sets the maximum value (top edge) of the color axis.
Range: −100 to +100 dB.
Full Scale. Sets Color Stop to 0 (zero) and Color Scale to 100 dBm.
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802.11n (nx1) Analysis
Marker readout
• Horizontal value: Time (s)
• Vertical value: EVM (%)
Modulation type
The Select Subcarrier setting
in the Meas Setup menu
Subcarrier number setting
in the Meas Setup menu
(displayed when Select Subcarrier
is set to Single Subcarrier)
Preamble indicator: “Preamble On” is
displayed when one or more preambles are
enabled in Modulation Type Display Filter of
the Meas Setup menu.
Packet information
(refer to page 3-57)
Measurement readout
(refer to the table below)
EVM versus Time
The main view shows the EVM of carriers, or one or all subcarriers in a line graph,
as shown in Figure 3-43. The vertical axis represents EVM in percent and the
horizontal axis represents time in seconds.
Figure 3-43: EVM versus Time (main view)
The following table shows the measurement readout that is displayed on the left in
the main view:
Measurement readoutUnitDescription
EVM(rms)%, dBRMS value of EVM
(Peak @ time)%, dBPeak value of EVM at the time
Mag Error(rms)%, dBRMS value of Mag Error
(Peak @ time)%, dBPeak value of Mag Error at the time
Phase Error (rms)degrees or radiansRMS value of Phase Error
(Peak @ time)degrees or radiansPeak value of Phase Error at the time
Origin OffsetdBOrigin offset (IQ feedthrough)
1.
The time is relative to the last data point.
1
1
1
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Scale Menu.
The Scale menu for EVM versus Time has the following controls:
Aut o Scale. Sets the start value and the scale of the vertical axis automatically
to fit the waveform to the screen.
Horizontal Scale. Sets the range of the horizontal axis (time).
Horizontal Start. Sets the minimum value (left edge) of the horizontal axis.
NOTE.
The horizontal display range must be within the analysis range specified
using the Timing menu (refer to page 2-6).
Ver t ic al S c a l e . Sets the range of the vertical axis.
Refer to Table 3-12 for the setting range.
Vertical Start. When the measurement content is EVM, sets the minimum value
(bottom edge) of the vertical axis. Refer to Table 3-12 for the setting range.
Vertical Offset. When the measurement content is Mag Error or Phase Error, sets
the center value ((maximum + minimum) / 2) of the vertical axis.
Refer to Table 3-12 for the setting range.