User Manual

Loss/Gain Offset68P09255A57-2
Aug 2002
SC4812ET Optimization/ATP Manual Software Release R16.1.x.x
PRELIMINARY
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Loss/Gain Offset
Background
Proper test equipment setup ensures that the test equipment and
associated test cables do not introduce measurement errors, and that
measurements are correct.
NOTE
If the test set being used to interface with the BTS has been
calibrated and maintained as a set, this procedure does not need
to be performed. (Test Set includes LMF terminal,
communications test set, additional test equipment, associated
test cables, and adapters.)
This procedure must be performed prior to beginning the optimization.
Verify all test equipment (including all associated test cables and
adapters actually used to interface all test equipment and the BTS) has
been calibrated and maintained as a set.
CAUTION
If any piece of test equipment, test cable, or RF adapter, that
makes up the calibrated test equipment set, has been replaced,
re-calibration must be performed. Failure to do so can introduce
measurement errors, resulting in incorrect measurements and
degradation to system performance.
NOTE
Calibration of the communications test set (or equivalent test
equipment) must be performed at the site before calibrating the
overall test set. Calibrate the test equipment after it has been
allowed to warm-up and stabilize for a minimum of 60 minutes.
Purpose
These procedures access the CDMA LMF automated calibration routine
used to determine the path losses of the supported communications
analyzer, power meter, associated test cables, and (if used) antenna
switch that make up the overall calibrated test set. After calibration, the
gain/loss offset values are stored in a test measurement offset file on the
CDMA LMF.
GPIB Addresses
GPIB addresses can range from 1 through 30. The LMF will accept any
address in that range, but the numbers entered in the LMF Options
window GPIB address box must match the addresses of the test
equipment. Motorola recommends using 1 for a CDMA signal generator,
13 for a power meter, and 18 for a communications system analyzer. To
verify and, if necessary, change the GPIB addresses of the test
equipment, refer to the Setting GPIB Addresses section of Appendix F.
Selecting Test Equipment
Use LMF Options from the Options menu list to select test equipment
automatically (using the autodetect feature) or manually.
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