User's Manual

Power Delta Calibration – continued
FEB 2005 1X SC 4812T Lite BTS Optimization/ATP H-15
PRELIMINARY
Table H-4: HP 8921A Power Delta Calibration Procedure
n ActionStep
7 Connect the short RF Cable between the source HP 8921A Duplex Out Port and the measuring
HP 8921A RF–IN Port.
– Refer to Figure H-8.
8 Ensure that the source HP 8921A Settings are the same as in Step 3.
9 Set the measuring HP 8921A as follows:
– Measure Mode to CDMA Anl
– Frequency to the CDMA Calibration Target Frequency
– Input Attenuation to 0 dB
– Input Port to RF–IN
– Gain to Auto
– Analyzer Direction to Fwd
10 Turn on the source HP 8921A Signal Output.
11 Measure and record the Channel Power Reading on the measuring HP 8921A as Result B.
B ________________________
12 Turn off the source HP 8921A Signal Output and disconnect the equipment.
13 Compute the Delta between HP437 and HP 8921A using the following formula.
Delta = A – B
Example: Delta = –0.70 dBm – (–1.25 dBm) = 0.55 dBm
Example: Delta = 0.26 dBm – 0.55 dBm = –0.29 dBm
NOTE
These examples are included to show the mathematics and do not represent actual readings.
NOTE
Add this Delta Value to the TX Cable Loss Value during In–Service Calibration.
– Refer to Step 4 in Table H-6.
Short RF Cable
HP 8921A
DUPLEX
OUT
HP437B
Power
Sensor
SENSOR
FW00801
Figure H-7: Delta Calibration Set–up – HP 8921A to HP437
H