Agilent Technologies E4428C, Руководство пользователя

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Chapter 16 501
W-CDMA Uplink Digital Modulation for Receiver Test
Overload Testing with Multiple PRACHs—Multiple ESGs
Sync Pulse signal from ESG 1, then its frame interval selection, if incorrect, may cause only a temporary
out of synchronization condition that is self-corrected. This is because ESG 2 is synchronized with ESG
1 and not directly with the BTS. See
“PRACH Synchronization” on page 566 and “Frame Sync Trigger
Status Indicator” on page 567 for more information.
Figure 16-35 Out of Synchronization Annunciator
6. Press
Return
>
Return
>
PhyCH Setup
>
PRACH Trigger Source Immedi Trigger
to Trigger.
Using the task, “Controlling the PRACH Transmission” on page 482 , you can set the number of 80 ms
period repetitions for a finite number of PRACH transmissions, or using the infinity selection, you can
enable a continuous PRACH transmission once the PRACH start trigger is received by the ESG.
NOTE
In order to have a finite number of transmitted 80 ms periods, you will need to ensure that
the PRACH trigger source is disabled once the PRACH transmission starts. If the trigger
source is not disabled, the PRACH signal will retrigger after the entered number of 80 ms
periods are transmitted.
Figure 16-36 shows the frame trigger menus after all selections have been completed. Your selection for the
Frame Clock Interval may be different than what is shown. If you have kept your PRACH trigger source
active, you will see the RACH Trg annunciator gray-out intermittently as the transmission from the trigger
expires and a new trigger is acquired.
Out of Sync
Annunciator