ZXG10 BS21 (V2.2) Compact Outdoor BTS for GSM Maintenance Manual
166
Confidential and Proprietary Information of ZTE CORPORATION
6.
Troubleshooting
i.
Check the operation record to confirm whether parameters that
influence the network running are modified recently, such as the
handover parameter, the parameter of the adjacent cell and power
control parameter.
ii.
Open the OMCR dynamic data management. Select an appropriate
time when the traffic is not too large or too little and then block
TCHs of all carriers except one carrier in dynamic data
management by blocking the logic channels (be careful not to block
SDCCH). Carefully observe (using the tracing function) the
occupancy of the time slot of the carrier (using a counter to
observe it every five minutes).
iii.
If a time slot TCH is found to be transitorily occupied (within 10
seconds), consider whether faulty time slots occur at the carrier.
Remotely reset the carrier, and observe it again. If still so, go to
the site to check the alarms of the carrier. Replace the carrier
module when necessary.
iv.
If no alarms occur at the carrier, check whether the receiving RF
cables of the two RXs of ETRM are reliably connected with the RF of
the divider.
v.
Observe the level-1 alarm indicator of the SWR1 standing wave
ratio on the AEM panel. If it is on, test the standing wave ratio of
the combiner output interface. If abnormal, go on to check the
standing wave ratio of the jumper, master feeder and antenna
section by section until the reason why it gets worse is found:
Whether the connectors between the set top jumper, master feeder
and antenna are in poor contact, or the water leakage caused by
poor encapsulation.
vi.
Inquire the transmission equipment room whether transmission
alarms exist. Check whether the transmission grounding is good
enough and whether transmission alarms occur in the TIC board of
BSC and the CMM at the BTS side. In addition, conduct
transmission bit error test when necessary.
vii.
Check whether other new antennas or obstacles exist around the
antenna. If yes, adjust the azimuth angle and height of the antenna
in time to lessen the influence.
viii.
Check whether atrocious weather occurs and the antenna feeder
system is altered before the call drop rate of the cell rises. If yes,
please check whether the azimuth angle and pitch angle of the
antenna are normal. If abnormal, adjust them.
ix.
Check whether co-frequency interference occurs, if yes, please
adjust the frequency.
7.
Precautions
None
