User's Manual

Basic Troubleshooting – RF Path Fault Isolation
PRELIMINARY
1X SCt4812ET Lite BTS Optimization/ATP
08/01/2001
6-12
Overview
The optimization (RF path characterization or calibration) and
post-calibration (audit) procedures measure and limit-check the BTS
reported transmit and receive levels of the path from each BBX2 to the
back of the frame. When a fault is detected, it is specific to a receive or
transmit path. The troubleshooting process in this section determines the
most probable cause of the fault.
As the calibration and audit tests are performed, results are displayed in
the LMF test status report window. When faults are encountered, the test
procedure in progress continues running and displaying any further
faults. If it appears that there are major faults, the test can be aborted.
The test results can be saved to a
bts–<#>.rpt file in the
wlmf\cdma\bts–<#> folder. To do this, close the test status report
window using the Save Results button.
Closing the test status report window with the Dismiss
button will delete the test results without saving them.
IMPORTANT
*
If a test is re–run or a new calibration, audit, or test is run and the results
are saved, the previous test results in the
bts–<#>.rpt file are
overwritten. To prevent losing previous test results in the
bts–<#>.rpt
file, refer to the procedure in Table 4-10 before performing further
testing with the LMF.
If there are major faults, recheck the test equipment attachments for
errors. If none are found, close the test status report window using the
Save Results button, and save the contents of the resulting
bts–<#>.rpt file as described in Table 4-10. Also, note other specifics
about the failure, and proceed with the fault isolation procedure.
If Every Test Fails
Check the calibration equipment for proper operation by manually
setting the signal generator output attenuator to the lowest output power
setting. Connect the output port to the spectrum analyzer RF input port.
Set the signal generator output attenuator to –90 dBm, and switch on the
RF output. Verify that the spectrum analyzer can receive the signal,
indicate the correct signal strength (accounting for the cable insertion
loss), and indicate the approximate frequency.
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