Huawei Airbridge cBTS3612 Maintenance Manual page 24

On-site Maintenance Manual
Airbridge cBTS3612 CDMA Base Station
V.
Check receiving channel
If we can see from the OMC console the logic configuration for
the cell has been completed, but the MS still can not connect to the
network, we can then check whether the receiving channel is
working properly.
If the BTS receiving channel is not working properly, it will result
in heavy bit errors. As a result, the MS will lose network connection
frequently. When the MS switches on, it will send a switch-on
registration message to the BTS. Due to the receiving channel failure,
the BTS is unable to receive the registration message and thus will
not send the response back to the MS, this will result in the MS
registration failure. When the registration fails, the MS will enter the
system confirmation substate and start recapturing the network,
when the network is captured, the MS will again activate the
switch-on registration... this will go on and the MS is still unable to
connect to the network.
We can use the CDMA test MS to trace the air interface
message: if the MS has sent the registration message and does not
receive the BTS response, the BTS inverse receiving channel must
be faulty.
If there is a problem with the receiving channel, we can go
through the following steps as well as checking the relevant
indicators, board status and alarm messages, etc. to locate it:
Whether the CDU (or DFU, or DDU), RLDU and BTRM are
l
secured in place, or whether the panel screws are all
tightened;
Whether the antenna and feeder is connected properly;
l
Chapter 2 General Fault
2-5
Processing