
Chapter 15 415
W-CDMA Uplink Digital Modulation for Receiver Test
DPCH
Configuring the E4440A
This task builds upon “Configuring the E4440A for Viewing the DPCCH/DPDCH Output” on
page 406.
1. Select the time domain measurement.
Press
More 1 of 2 > Waveform (Time Domain).
2. Set a Sweep time that lets you view the signal parameters.
Press
Meas Setup > Sweep Time > 100 > ms.
3. Set the resolution bandwidth for a faster response time that captures the signal
components.
Press
Res BW > 500 > kHz.
4. Trigger the signal analyzer from the rear panel input using the supplied ESG trigger
signal.
Press
Trig Source > Ext Rear.
5. Zoom in on the RF Envelope display
Press
Zoom.
You can now see the compressed signal moving across the PSA display.
Adjusting the Number of Gap Patterns
This task builds upon “Setting Up the Compressed Mode” on page 411.
This task will set up the ESG so that the transmitted gap patterns have a finite repetition.
This will enable you to have a clearer view of how the compressed signal parameters affect the
transmission.
1. Select the number of transmitted gap patterns.
a. Highlight the TGPRC field.
b. Press
5 > Enter.
2. Press
Apply Channel Setup > Compressed Mode Start Trigger.
The Comp Trg annunciator comes on and then goes off after 5 gap pattern transmissions.
This indicates that the compressed mode trigger is no longer active and the ESG has quit
transmitting compressed frames.
Notice that the frame pattern is now easily viewed on the E4440A display and is shown in
Figure 15-43. This figure also points out some of the compressed mode parameters as they
appear on the signal.
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