User`s guide

Chapter 14 333
W-CDMA Downlink Digital Modulation for Receiver Test
Using W-CDMA Downlink
Setting Equal Channel Powers
This task teaches you how to set the relative power level for all active channels to be equal, for
a total power level of 0 dB. The normalized relative power level of each channel depends on
the number of active channels. This task is an alternative to scaling to 0 dB.
Press
Adjust Code Domain Power > Equal Powers.
All active channels have now been set to equal powers. Figure 14-5 shows the displayed
normalized relative power levels after the
Equal Powers softkey is pressed with seven active
channels. Notice also that the displayed total power shows a residual value of 0.02 dB due to
decimal rounding.
Figure 14-5 Equal Powers
Managing Noise
The tasks in this procedure build upon the previous procedure.
The following tasks teach you how to set the overall carrier-to-noise (C/N) ratio for the
downlink W-CDMA setup and to set the EcNo value for individual physical channels.
• “Setting the Carrier to Noise Ratio” on page 333
• “Setting EcNo” on page 334
Setting the Carrier to Noise Ratio
1. Press
Mode Setup to return to the top-level real-time W-CDMA menu.
2. Press
Link Control > 8 > Enter > Channel State Off On to On.
3. Press
PhyCH Setup.
4. Move the cursor to highlight the C/N value field.
5. Press
10 > dB.
NOTE Noise values less than 10 dB may not be visible on a spectrum analyzer.
Displayed Power Levels
After Equal Powers