User Manual
WCA230A & WCA280A Option 22
W-CDMA Downlink Analysis Software
071-1475-00
This document applies to firmware version 2.0
and above.
www.tektronix.com
Copyright © Tektronix Japan, Ltd. All rights reserved.
Copyright © Tektronix, Inc. All rights reserved.
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Tektronix, Inc., P.O. Box 500, Beaverton, OR 97077
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In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration of the
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Tektronix warrants that the media on which this software product is furnished and the encoding of the programs on the
media will be free from defects in materials and workmanship for a period of three (3) months from the date of shipment.
If a medium or encoding proves defective during the warranty period, Tektronix will provide a replacement in exchange
for the defective medium. Except as to the media on which this software product is furnished, this software product is
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In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration of the
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THIS WARRANTY IS GIVEN BY TEKTRONIX 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
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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.
Table of Contents
Getting Started
Operating Basics
Preface v. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Definition of Analysis 1–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Measurement Functions 1–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Measurement Process 1–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Modulation Analysis Measurement Items 1–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Measurement Menu 1–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Basic Operation in the S/A Mode 2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Measurement Procedure 2–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ACLR Measurement 2–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Basic Operation in the Demod Mode 2–5. . . . . . . . . . . . . . . . . . . . . . . . . . .
Measurement Procedure 2–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Meas Setup Menu 2–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Scale and Format of View 2–11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Code Domain Power 2–14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Codogram 2–16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Code Power vs. Time Slot 2–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Code Power vs. Symbol 2–20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Symbol Constellation 2–22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Symbol EVM 2–23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Symbol Eye Diagram 2–25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Symbol Table 2–26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Modulation Accuracy 2–27. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Syntax and Commands
Command Groups 3–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Functional Groups 3–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
:CONFigure Commands 3–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
:DISPlay Commands 3–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
:FETCh Commands 3–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
:READ Commands 3–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
:SENSe Commands 3–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
:CONFigure Commands 3–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
:DISPlay Commands 3–9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
:FETCh Commands 3–39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
:READ Commands 3–47. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
:SENSe Commands 3–49. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
WCA230A & WCA280A Option 22 User Manual
i
Table of Contents
Appendices
Index
Appendix A: Factory Initialization Settings A–1. . . . . . . . . . . . . . . . . . . . .
Appendix B: Scale Setting Range B–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Appendix C: SCPI Conformance Information C–1. . . . . . . . . . . . . . . . . . .
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WCA230A & WCA280A Option 22 User Manual
List of Figures
Table of Contents
Figure 1–1: W-CDMA downlink analysis display 1–1. . . . . . . . . . . . . . . .
Figure 1–2: W-CDMA downlink measurement menus 1–4. . . . . . . . . . . .
Figure 2–1: W-CDMA ACLR measurement 2–4. . . . . . . . . . . . . . . . . . . .
Figure 2–2: Code domain power measurement example 2–7. . . . . . . . . . .
Figure 2–3: Time slot table 2–11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 2–4: Code domain power versus Short code 2–15. . . . . . . . . . . . . . .
Figure 2–5: Power codogram 2–17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 2–6: Code domain power versus Time slot 2–19. . . . . . . . . . . . . . . .
Figure 2–7: Code domain power versus Symbol 2–21. . . . . . . . . . . . . . . . .
Figure 2–8: Symbol constellation 2–22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 2–9: Symbol EVM 2–24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 2–10: Symbol eye diagram 2–25. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 2–11: Symbol table 2–26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 2–12: Modulation accuracy 2–27. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 3–1: :DISPlay:AC3Gpp command setting 3–10. . . . . . . . . . . . . . . .
Figure 3–2: :DISPlay:DL3Gpp command setting 3–15. . . . . . . . . . . . . . . .
WCA230A & WCA280A Option 22 User Manual
iii
Table of Contents
List of Tables
Table 1–1: Additional functions in Option 22 1–1. . . . . . . . . . . . . . . . . . .
Table 1–2: W-CDMA downlink signal parameters 1–2. . . . . . . . . . . . . . .
Table 3–1: Measurement modes added in Option 22 3–1. . . . . . . . . . . . .
Table 3–2: List of command groups 3–2. . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 3–3: :CONFigure commands 3–3. . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 3–4: :DISPlay commands 3–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 3–5: :FETCh commands 3–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 3–6: :READ commands 3–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 3–7: :SENSe commands 3–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 3–8: :DISPlay command subgroups 3–9. . . . . . . . . . . . . . . . . . . . . .
Table 3–9: Symbol rate settings 3–17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 3–10: Main view display formats 3–20. . . . . . . . . . . . . . . . . . . . . . . .
Table 3–11: Subview display formats 3–30. . . . . . . . . . . . . . . . . . . . . . . . . .
Table 3–12: Queried information on the W-CDMA downlink
analysis results 3–41. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 3–13: :SENSe command subgroups 3–49. . . . . . . . . . . . . . . . . . . . . .
Table A–1: Factory initialization settiings — :DISPlay commands A–1.
Table A–2: Factory initialization settiings — :SENSe commands A–2. . .
Table B–1: Display format and scale B–1. . . . . . . . . . . . . . . . . . . . . . . . . .
Table C–1: SCPI conformance information — :CONFigure
commands C–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table C–2: SCPI conformance information — :DISPlay commands C–2
Table C–3: SCPI conformance information — :FETCh commands C–3.
Table C–4: SCPI conformance information — :READ commands C–3.
Table C–5: SCPI conformance information — :SENSe commands C–4.
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WCA230A & WCA280A Option 22 User Manual
Preface
About This Manual
This manual describes how to use the WCA230A and WCA280A Option 22
W-CDMA Downlink Analysis Software. For details on the standard functions of
the analyzer, refer to the WCA230A and WCA280A Wireless Communication
Analyzers User Manual.
The manual consists of the following sections:
H Getting Started describes the overview of the W-CDMA downlink analysis.
H Operating Basics explains the menu functions and measurement procedures.
H Syntax and Commands presents descriptions of the GPIB commands
provided in Option 22.
H Appendices provide additional information including factory initialization
settings, scale setting ranges, and SCPI conformance informatin.
Related Documents
The following documents are also available for the analyzer.
H WCA230A and WCA280A User Manual
(Standard accessory; Tektronix part number 071-1253-XX)
Describes how to install the analyzer and how to work with the menus, and
details the standard functions. Also shows the specifications.
H WCA230A and WCA280A Programmer Manual
(Standard accessory; Tektronix part number 071-1255-XX)
Contains an alphabetical listing of the programming commands and other
information related to controlling the analyzer over the GPIB interface.
WCA230A & WCA280A Option 22 User Manual
v
Preface
Conventions
This manual uses the following conventions:
H Front-panel button and control labels are printed in the manual in upper case
text. For example, SPAN, PEAK, PRINT. If it is part of a procedure, the
button or control label is printed in boldface. For example:
Press SPAN.
H To easily find buttons on the front panel, the area name label is printed together
with the button by concatenating with a colon (:), as in MODE: DEMOD,
VIEW: SCALE, MARKERS: SELECT, etc. For example:
Press the MODE: DEMOD key.
H Menu and on-screen form titles are printed in the manual in the same case
(initial capitals) as they appear on the analyzer screen, such as Span, Source,
and Channel Power. If it is part of a procedure, the menu title is shown in
boldface. For example:
Press the Source side key.
H A list of keys, controls, and/or menu items separated by an arrow symbol
(Õ) indicates the order in which to perform the listed tasks. For example:
Select RBW/FFT Õ Filter Shape...Õ Gaussian.
vi
WCA230A & WCA280A Option 22 User Manual
Contacting Tektronix
Preface
Phone 1-800-833-9200*
Address Tektronix, Inc.
Department or name (if known)
14200 SW Karl Braun Drive
P.O. Box 500
Beaverton, OR 97077
USA
Web site www.tektronix.com
Sales support 1-800-833-9200, select option 1*
Service support 1-800-833-9200, select option 2*
Technical support Email: techsupport@tektronix.com
1-800-833-9200, select option 3*
6:00 a.m. – 5:00 p.m. Pacific time
* This phone number is toll free in North America. After office hours, please leave a
voice mail message.
Outside North America, contact a Tektronix sales office or distributor; see the
Tektronix web site for a list of offices.
WCA230A & WCA280A Option 22 User Manual
vii
Preface
viii
WCA230A & WCA280A Option 22 User Manual
Getting Started
Getting Started
This section outlines the downlink analysis according to the W-CDMA standard
using Option 22. Table 1–1 summarizes the additional functions in Option 22 by
the measurement mode.
Table 1-1: Additional functions in Option 22
Measurement mode Additional functions
S/A (spectrum analysis) WĆCDMA ACLR measurement
Demod (modulation analysis) Nine measurement functions, including code domain power
Time (time analysis) None
Figure 1–1 shows an example of the downlink analysis in the Demod mode.
Figure 1-1: WĆCDMA downlink analysis display
WCA230A & WCA280A Option 22 User Manual
1-1
Getting Started
Definition of Analysis
This instrument performs measurements according to the W-CDMA downlink
signal parameters shown in Table 1–2.
Table 1-2: WĆCDMA downlink signal parameters
Item Description
Chip rate 3.84 Mcps
Symbol rate 7.5, 15, 30, 60, 120, 240,Ă480,Ă960, and 1920 ksps
Maximum number of channels 512
Frame structure Time slot: 666.7 ms
Scrambling code Gold code using M series by generator polynomial 18Ăbits
Channelization code Hierarchical orthogonal code series based on the
combination of chip rate and symbol rate
Modulation method of each channel QPSK
Measurement Functions
Baseband filter Root cosine of a = 0.22 (default)
Can be set in the range of 0.0001 ≤ a ≤ 1
The analyzer has the following measurement functions:
H Code domain power
Measures the power relative to the total power for each channel.
Multi-rate is supported and up to 512 channels can be measured.
H Code domain power vs. Time
Measures the relative power at symbol points for each channel in time series.
H Code domain power spectrogram
Measures the code domain power continuously for up to 150 slots (0.1 sec)
and displays spectrogram for each slot.
H Vector/Constellation
Measures the vector loci and chip points for all signals as well as constellation at symbol points for each channel.
H Modulation accuracy
Measures EVM (Error Vector Magnitude), amplitude and phase errors,
waveform quality, and origin offset for each channel.
Measures PCDE (Peak Code Domain Error), amplitude, frequency, and
phase errors; waveform quality; and origin offset for each time slot.
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WCA230A & WCA280A Option 22 User Manual
Measurement Process
The internal process for the W-CDMA downlink analysis is as follows:
1. Perform the flatness correction and filtering.
2. Establish the synchronization with P-SCH.
3. Determine the range of scrambling code numbers with S-SCH.
4. Fix the scrambling code number and the phase.
5. Correct the frequency and the phase.
6. Perform high-speed Hadamard transformation.
7. Calculate the power for each symbol on all channels.
Modulation Analysis Measurement Items
Getting Started
Use the Measure menu to select the measurement items provided in the Demod
(modulation analysis) mode:
H Code Domain Power. Displays code domain power for each short code.
H Power Codogram. Displays code domain power with a spectrogram.
H Code Power versus Time Slot. Displays code domain power for each
time slot.
H Code Power versus Symbol. Displays code domain power for each symbol.
H Symbol Constellation. Displays a symbol constellation.
H Symbol EVM. Displays EVM for each symbol.
H Symbol Eye Diagram. Displays a symbol eye diagram.
H Symbol Table. Displays a symbol table.
H Modulation Accuracy. Displays constellation and measurement results for
each time slot. The results were obtained before de-spread occurred.
WCA230A & WCA280A Option 22 User Manual
1-3
Getting Started
Measurement Menu
Figure 1–2 shows the measurement menus added in Option 22.
Standard... WĆCDMAĆDL Channel Power
ACLR
OBW
EBW
Carrier Frequency
Standard...
WĆCDMAĆDL
Code Domain Power
Power Codogram
Code Power versus Time Slot
Code Power versus Symbol
Symbol Constellation
Symbol EVM
Symbol Eye Diagram
Symbol Table
Modulation Accuracy
Figure 1-2: WĆCDMA downlink measurement menus
The following sections provide the measurement procedures.
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WCA230A & WCA280A Option 22 User Manual
Operating Basics
Basic Operation in the S/A Mode
This section describes the basic operation in the S/A (Spectrum Analysis) mode.
WCA230A & WCA280A Option 22 User Manual
2-1
Basic Operation in the S/A Mode
Measurement Procedure
Use the following procedure for a spectrum measurement in the S/A mode.
1. Press the S/A key on the front panel.
2. Press the side key Standard...Õ W-CDMA-DL.
3. Press the FREQUENCY/CHANNEL key on the front panel and set
NOTE. For details on setting frequency, span, and amplitude, refer to the
WCA230A and WCA280A User Manual.
frequency.
If you use the channel table, do these steps:
a. Press the Channel Table... side key and select W-CDMA-DL.
b. Press the Channel side key and select a channel by turning the general
purpose knob.
The center frequency is set to the value corresponding to the channel.
4. Set span and amplitude appropriately.
NOTE. If the input level is too high, A/D OVERFLOW displays in the red box at
the center top of the screen. If this occurs, raise the reference level.
5. Press the MEASURE key on the front panel and select a measurement item:
H Channel Power
H ACLR (Adjacent Channel Leakage Power Ratio)
H OBW (Occupied Bandwidth)
H EBW (Emission Bandwidth)
H Carrier Frequency
NOTE. All the measurement items except ACLR are the same as in normal
spectrum analysis. For details on these items, refer to the WCA230A and
WCA280A User Manual. For the ACLR measurement procedure, refer to
page 2–3.
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WCA230A & WCA280A Option 22 User Manual
ACLR Measurement
Basic Operation in the S/A Mode
The ACLR (Adjacent Channel Leakage Power Ratio) measurement according to
the W-CDMA standard is based on the ACPR measurement function in the
normal spectrum analysis. For the basics, refer to ACPR Measurement in the
WCA230A and WCA280A User Manual.
The following settings are fixed according to the W-CDMA standard:
Span 25 MHz. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Main channel measurement bandwidth (Main Chan BW) 3.84 MHz. . . . .
Adjacent channel measurement bandwidth (Adj Chan BW) 3.84 MHz. . .
Channel spacing (Chan Spacing) 5 MHz. . . . . . . . . . . . . . . . . . . . . . . . .
After selecting ACLR in the procedure on page 2–2, set the parameters in the
Measurement Setup menu as follows:
Measurement Setup Menu
The Measurement Setup menu for the ACLR measurement contains the
following parameters:
Measurement Filter Shape... Selects a filter shape:
H Rect (rectangle)
H RootNyquist (Root Nyquist, default)
Rolloff Ratio. Sets the roll-off value when the filter is root Nyquist.
Range: 0.0001 to 1 (default: 0.22)
nd
2
Adj Channel Gain. Because the power of the second adjacent channel is
normally much smaller than the main channel, measurement with the same gain
causes a larger error. To enhance accuracy, raise the gain of the second adjacent
channel inside the analyzer. Set the gain value here.
Range: 3 to 15 dB (default: 5dB)
The upper limit of the range may be smaller than 15 dB, depending on the
amplitude setting. This setting does not affect the waveform display.
WCA230A & WCA280A Option 22 User Manual
2-3
Basic Operation in the S/A Mode
Figure 2–1 shows an example of the ACLR measurement. Measured values are
displayed in the lower part of the screen.
Main Chan Upper 1 Upper 2Lower 1Lower 2
Figure 2-1: WĆCDMA ACLR measurement
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WCA230A & WCA280A Option 22 User Manual
Basic Operation in the Demod Mode
This section describes the basic operation in the Demod (Modulation Analysis)
mode. The W-CDMA downlink analysis in the Demod mode is based on the
digital modulation analysis function. For the digital modulation analysis, refer to
the WCA230A and WCA280A User Manual.
Measurement Procedure
The following procedure shows you how to acquire data of multiple slots in
advance, measure continuous data, and obtain continuous code domain power:
1. Press the DEMOD key on the front panel.
2. Press the side key Standard...Õ W-CDMA-DL.
3. Press the FREQUENCY/CHANNEL key on the front panel to set
frequency.
NOTE. For details on setting frequency, span, and amplitude, refer to the
WCA230A and WCA280A User Manual.
If you use the channel table, do these steps:
a. Press the Channel Table... side key and select W-CDMA-DL.
b. Press the Channel side key and select a channel by rotating the general
purpose knob.
The center frequency is set to the value corresponding to the channel.
4. Set span and amplitude appropriately.
NOTE. If the input level is too high, A/D OVERFLOW displays in the red box at
the center top of the screen. At this time, raise the reference level.
WCA230A & WCA280A Option 22 User Manual
2-5
Basic Operation in the Demod Mode
5. Press the TIMING key on the front panel and then the Acquisition Length
side key to set the time length to acquire one block.
Suppose that one block contains M frames; the acquisition length is
calculated with this equation:
(One block acquisition length) = M (One frame acquisition length)
One frame acquisition length is determined by span and indicated on the
Spectrum Length side key.
The number of frames M required for measuring N slots must meet the
following condition:
M > K (N + 1.2) + 1
where
K =16.7 (for the span of 20 MHz and 15 MHz)
8.34 (for the span of 10 MHz)
4.17 (for the span of 5 MHz)
6. After acquiring measurement data, stop the data acquisition.
If you are acquiring data in the continuous mode, press the RUN/STOP key.
7. Press the MEASURE key on the front panel and select measurement items.
For example, press the Power Codogram side key to observe the code domain power spectrogram.
8. Press the MEAS SETUP key on the front panel and set the measurement
parameters. Refer to page 2–8 for details of the Meas Setup menu.
9. Set the analysis range in the overview.
Refer to the WCA230A and WCA280A User Manual for the details.
10. Press the Analyze side key to perform measurement for the frames in the
analysis range. The measurement result and waveform are displayed in the
main view.
Change the scale and format of the view as needed. Refer to page 2–11 for
setting views specific to the W-CDMA downlink analysis.
11. If the level of input signals is low, the waveform may not be displayed
correctly. In this case, perform the following procedure:
NOTE. Correct W-CDMA downlink signal analysis cannot be performed if the
P-SCH, S-SCH, and PCPICH channels are too low to be detected. An error
occurs when one of these channel levels is lower than about 1/10
th
the sum of
other channel levels. In this case, set Scrambling Code Search to Off and specify
the scrambling code with Scrambling Code.
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WCA230A & WCA280A Option 22 User Manual
Basic Operation in the Demod Mode
a. Press the MEAS SETUP key on the front panel.
b. Press the Modulation Parameters... side key.
c. Press the Scrambling Code Search side key to select Off.
d. Press the Scrambling Code side key and enter the scrambling code.
The analyzer performs measurement with the value set here in place of
detecting the scrambling code.
e. Press the MEAS SETUP key on the front panel.
f. Press the Analyze side key to perform measurement for the frames in the
analysis range.
Figure 2–2 shows an example of the code domain power measurement.
Figure 2-2: Code domain power measurement example
WCA230A & WCA280A Option 22 User Manual
2-7
Basic Operation in the Demod Mode
Meas Setup Menu
The Meas Setup menu for the W-CDMA downlink analysis contains the
following items:
Analyze
Modulation Parameters...
Performs analysis for time slots in the analysis range.
Sets a measurement parameter to a non-standard value.
The following controls are provided:
Scrambling Code Search. Selects whether to perform analysis by detecting a
scrambling code from input signals.
H On. Detects a scrambling code from the input signal to perform the
measurement.
H Off. Performs measurement using the scrambling code that has been set with
Scrambling Code described below.
Refer to Note on page 2–6.
Scrambling Code. Sets the scrambling code number when you select Off in
Scrambling Code Search. Range: 0 to 24575.
The analyzer performs measurement using the set scrambling code.
Use SCH Part. Selects whether to include or exclude the SCH portion when
calculating the code domain power.
2-8
H On. Calculates the code domain power by including the SCH portion.
H Off. Default. Calculates the code domain power by excluding the SCH
portion.
Composite. Determines whether to perform the composite analysis (automatic
detection of symbol rate).
H On. Specifies that the composite analysis is performed.
H Off. Specifies that the composite analysis is not performed.
NOTE. You should usually specify that composite analysis is performed. If a
normal analysis does not result, select Off in this command and select a specific
symbol rate with Symbol Rate in the View: Define menu.
WCA230A & WCA280A Option 22 User Manual
Basic Operation in the Demod Mode
Measurement Filter... Selects a filter for demodulating digitally-modulated
signals:
H None (no filter)
H RootRaisedCosine
Reference Filter... Selects a filter for creating reference data:
H None (no filter)
H RaisedCosine
H Gaussian
For the filters, refer to Process Flow of Digitally-Modulated Signal in the
WCA230A and WCA280A User Manual.
Filter Parameter. Sets the a/BT value for Measurement Filter and Reference Filter
described above. Range: 0.0001 to 1.
Auto Carrier
Frequency Offset
Selects whether to detect the carrier automatically.
H On. Default. Automatically detects the carrier for every frame.
The error from the center frequency is shown on the Freq Error side key.
H Off. Sets the carrier frequency using Frequency Offset described below.
Sets the carrier frequency when Off is selected in Auto Carrier.
Input the carrier offset from the center frequency.
WCA230A & WCA280A Option 22 User Manual
2-9
Basic Operation in the Demod Mode
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WCA230A & WCA280A Option 22 User Manual
Scale and Format of View
The following main views are specific for the measurement items of the
W-CDMA downlink analysis in Demod mode:
H Code domain power
H Power codogram
H Code power vs. Time slot
H Code power vs. Symbol
H Symbol constellation
H Symbol EVM
H Symbol eye diagram
H Symbol table
H Modulation accuracy
Each view and its specific menu are described on the following pages. In the
main view, the time slot table shown in Figure 2–3 is displayed in addition to
waveform and measurement results.
Time slot number in analysis range
(0 is the last number.)
Figure 2-3: Time slot table
Time slot number in radio frame
SSCH (Secondary Synchronization Channel)
SCG (Scrambling Code Group)
Scrambling code number
WCA230A & WCA280A Option 22 User Manual
2-11
Scale and Format of View
View: Define Menu
The View: Define menu is common to all main views of the W-CDMA downlink
measurement items. It contains the following controls:
Show Views. Selects the view style:
H Single. Displays only the view selected by the VIEW: SELECT key.
H Multi. Default. Displays the overview, subview, and main view.
Overview Content... Selects a view to display in the overview:
H Waveform (power versus time)
H Spectrogram
Subview Content... Selects a view to display in the subview:
H Spectrum
H Code Domain Power
H Power Codogram
H Code Power versus Time Slot
H Code Power versus Symbol
H Symbol Constellation
H Symbol EVM
H Symbol Eye Diagram
H Symbol Table
H Modulation Accuracy
Time Slot. Sets a time slot number to position the marker.
Range: 0 to number of slots – 1
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WCA230A & WCA280A Option 22 User Manual
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