Agilent Technologies E4428C, Руководство пользователя

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Chapter 16 469
W-CDMA Uplink Digital Modulation for Receiver Test
Generating a Single PRACH Signal
( Figure 16-17 on page 470 ) and base station connection diagram shown in the section, “Using the AICH
Feature with a Base Transceiver Station” on page 472 .
Using the AICH feature may turn the ESG ALC feature off. For reliable results, you may need to perform a
power search. Refer to
“Special Power Control Considerations When Using DPCCH/DPDCH in
Compressed Mode or PRACH” on page 570 before completing this procedure.
This procedure will teach you how to set up the AICH (acquisition indication channel) feature so that it
triggers the message part transmission. This procedure uses the ESG’s LF (low frequency) output to
simulate the AICH signal (TTL trigger), or if you prefer, an external source can be used. Connecting the
AICH trigger signal to the ESG requires the use of the rear panel AUX I/O connector. (See
“Rear Panel
Overview” on page 16 or “Rear Panel Overview” on page 37 for more information on the AUX I/O
connector.) An adapter will be needed to make the connection between the LF OUTPUT and pin 17 on the
AUX I/O connector.
Finding the Rear Panel Input for the AICH Signal
1. Press
Link Control
>
PRACH Rear Panel Setup
>
PRACH Input Signal Setup
.
2. Find which rear panel connector accepts the AICH trigger.
The listed connector (
Pattern trigger in 2
on
AUX pin 17
) is a pin on the AUX I/O connector.
Changing the PRACH Output Trigger
Press
Return
>
PRACH Output Signal Setup
>
More (1 of 3)
>
More (2 of 3)
>
PRACH Pulse(RPS23)
.
This is being done so you can view the message part transmission on the PSA as the AICH is received. The
trigger output is on the EVENT 1 rear panel connector.