Call failure caused by equipment problems

Call failure caused by equipment problems
Strictly speaking, equipment problems should be solved before network optimization, but actually a lot of equipment problems are found in optimization.
Typical phenomena
The problems are sudden: the previous network works normally, and the problems happen suddenly.
The problems are universal: after DT test, it can be found that the problems happen in large area.
Analyzing:
Inquire if there is hardware changing recently, like boards replacing or transmission changing and so on; Inquire if there is software changing recently, like the software version updating or parameters adjustment;

If there are software and hardware adjustment, check the adjustment and consider resuming these adjustments, observe if the problem will happen;

If there is no adjustment recently, start single cell checking and judge if there is problem in hardware;
Single cell checking can find the obvious equipment problem, but some secluded problems are hard to find. At this time, boards resetting and replacement can be used to locate the problem.

Solution:
Because the reason is equipment problem, so the solution can not be called as “optimization”, it is just like troubleshooting.
In troubleshooting, TRX, CHM, CCM, and antenna feeder system are the key points we should care for.
Note:
The operation for software and hardware should be very cautious. For commercial network, the operation should be carried out by operator’s engineers after operator’s permission;
All the operation for equipment should be after midnight, if there is problem in operation, everything should be resumed in time.