To Troubleshoot An Edge Signal - Agilent Technologies 89410A Operator's Manual

Using Digital Demodulation (Opt. AYA)

To troubleshoot an EDGE signal

This task shows you how to use the error-vector trace and the symbol
table to diagnose problems with an EDGE signal. To simulate an error
condition, the task uses the analyzer's source to mix a 5.1 MHz, –35 dbM
sine wave with the EDGE signal loaded in the previous task.
1.
Demodulate your EDGE signal as shown in the previous task.
2.
Make sure points/symbol are set to one:
Press [ ], [
Time points/symbol
3.
Mix the analyzer's source with your EDGE signal.
Connect a T-connector to the CHANNEL 1 input.
Connect the analyzer's SOURCE output to the T-connector.
Connect your EDGE signal to the T-connector.
4.
Configure the source to output a 5.01 MHz, –35 dbM, sine wave:
Press [ ]
Source
Press [ ], [ ], [
level –35 dbM
Press [ ], [ ], [
sine freq 5.01
Press [
source on]
5.
Display the error-vector in trace A and autoscale the trace:
Press [ ], [
A Measurement Data
Press [ ], [
Data Format
Press [ ],
Auto Scale
6.
Display two grids and put the symbol table in the lower trace.
Press [ ], [
Display two grids
Press [ ] (By default, the symbol table is in trace D).
D
The error-vector vector diagram and symbol table provide good insight
into the quality of your EDGE signal. The next step shows you another
useful display: the error-vector spectrum.
7.
Display the spectrum of the error-vector in trace A and auto-scale the trace.
Press [ ], [
A Measurement Data
Press ].
[Auto Scale
You use the same methods to troubleshoot an EDGE signal as you do
other types of digital signals. For example, you still use error parameters
in the symbol table to help you determine the quality of an EDGE signal.
The symbol table reports error parameters such as Mag Err (Magnitude
Error), Phase Err (Phase Error), Freq Err (Frequency Error), EVM (Error
Vector Magnitude), and SNR (Signal-to-Noise Ratio).
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enter
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error vector time
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polar IQ vector
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Ierror vector spectrum
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