saifan,
there is a high number of CHANNEL FAILURE on the TRX’s 2/3/5 of one BTS :
the CHANNEL FAILURE means that TCH CHANNEL are required on these TRX by the BSC, but MS can’t seem to access those TCH.
the reason for such failures are :
high interference
poor coverage
faulty hardware (TRX, combiner, ..)
handover problems
etc.
when you see such a high amount of failure (more than 20%), you must assume that your hardware is faulty. Bad coverage or interference cannot generate such high rate of failures (usually).
because it happens on many TRXs of one BTS, then perhaps not those 3 TRX’s are faulty, but one equipment that is shared by those three TRX.
i hope this is clearer 🙂
regards,
pix