Agilent Technologies E4428C, Руководство пользователя

Страница: 509 / 700

Chapter 16 485
W-CDMA Uplink Digital Modulation for Receiver Test
Setting Up a Multiple PRACH Signal
Figure 16-28 Tp-m Setting
a. Highlight the
Tp-m
(time from the preamble to the message part) field.
b. Press
4
>
Enter
.
The range for this field is 1 to 15.
You have now increased the distance from the for the Tp-m from three access slots (3.99 ms) to four
(5.32 ms). An access slot is 1.33 ms in length.
If you need to have a UE repeat its PRACH multiple times within the 80 ms time period, you may want
to keep the Tp-m to a minimum value. Since you are limited to 60 access slots (80 ms), an increase in the
Tp-m value further limits the number of times a UE’s PRACH can be repeated.
4. Press
Apply Channel Setup
.
When the
Apply Needed
annunciator appears, press the
Apply Channel Setup
softkey. You will not see a
change in the signal until you press this softkey.
Setting the Control Part Parameters
1. Select the message part control data.
a. Highlight the
Msg-Ctrl Data
field.
b. Press
Edit Item
.
Notice that you have a selection of different control information types with the factory default being
3GPP STD
(pilot bit pattern as stated in the 3G TS 25.211 V3.3.0 (2002-03). You can select a PN
sequence, FIX 4 pattern, or create your own control pilot information with the
User File
selection.
c. Ensure that
3GPP STD
is highlighted and press
Return
.
2. Set the TFCI (transport format combination indicator) bits.
a. Highlight the
TFCI Pattern
field.
b. Press
Edit Item
.
Notice that you have a selection of different TFCI patterns that you can choose from, including the
ability to create your own pattern (
User File
softkey). The base station uses the TFCI to determine
what transport channel configuration is being used. The TFCI pattern, relative to a transport channel
Message Part
10 ms TTI