Nokia 6680 RM-36, Руководство по обслуживанию

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22. Measure the WCDMA output power.
It should be around 21 dBm.
23. Click RF Stop and uncheck the "Max power limit" check box.
24. Repeat steps 19 to 23 for 19, +7, 0, -20 and –40 dBm levels.
The measured output power may not differ more than +-2 dB from the requested value at level +19dBm
and no more than +-4dB on lower levels.
Remember to stop the RF before sending new data.
Alternative steps
• Measure the wide range levels normally and write down the levels that are possible to measure.
• Click Finish.
• Click Options.
• Change the first wide range DAC value to 573 and change the number of tuning steps to 21.
• Change the spectrum analyzer reference level to –20 dBm and adjust the input attenuator to the lowest
value possible.
• In the "Wide Range" pane, click Tune and fill in the rest of values starting from the 19th level.
Tx band response calibration (WCDMA)
Context
Tx band response calibration is required to get compensation parameters for DSP algorithm in order for it to
handle frequency response variations (caused by SAW filter, PA and duplexer unidealities) in open loop power
control and maximum power limitation situations.
Steps
1. From the "Operating mode" dropdown menu, set mode to "Local".
2. From the Tuning menu, choose WCDMA -> Tx Band Response Calibration.
3. Setup the spectrum analyzer according to the following settings:
Frequency: 1950.3 MHz
Span: 100 MHz
Reference level offset: Cable attenu adapter attenuation
Reference level: 30 dBm
Input attenuation: Default
Resolution bandwidth: more than 4.7 MHz (i.e. 5MHz)
RM-36
RF Troubleshooting and Manual Tuning Guide
Nokia Customer Care
Issue 1 Company Confidential Page 7–55
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