- This topic has 10 replies, 1 voice, and was last updated 3 years, 5 months ago by bie.
6th May 2008 at 17:14 #52369Rizwan SaifiGuest
please do help me regarding the following.
I was told by OSS department that CHANNEL FAILURE is 52% on TRX2, 3 and TRX5 on GSM. Can anybody help me regarding its detail.
1. Why this alarm appears on TRX?
2. What are its effects?
3. How can it be avoided or fixed?
Thanx in advance.7th May 2008 at 07:18 #52370pixGuest
i would say that TRX 2, 3 and 5 are faulty, or maybe (more probably) they share an equipment that is faulty. I’d go for the combiner…
channel failure is a QOS Indicator, so it is not an alarm. It can be computed from BSS counters.9th May 2008 at 09:21 #52371Rizwan SaifiGuest
But i culd not understand your answer. Kindly describe in such an easy manner as you can. Also I want to inform tht there is no COMBINER attached to these TRXs.
Thanx in advance.9th May 2008 at 09:38 #52372pixGuest
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 :
faulty hardware (TRX, combiner, ..)
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 🙂
pix10th May 2008 at 06:43 #52373Rizwan SaifiGuest
Yup Clear n Thanx
But the stunning thing is that if we provide a HARD ReSET to the TRX, re-connect its SMA connectors and re-commission the cabinet, the CHANNEL FAILURE indicator exponentially comes down and even vanishes.
What do u say about it?
Thanx in advance.10th May 2008 at 07:23 #52374pixGuest
it proves that the software was “bugged”, and you cleared the problem by re-initializing the software.
that’s a very obvious cause of high channel failures. Usually, every time you measure a bad QoS, you got to do a software reset first (that’s easy, quick and readily available). Then you investigate other problems 🙂
I’m glad you fixed the problem 🙂
pix11th May 2008 at 17:20 #52375Rizwan SaifiGuest
Thanx once again
U mean Software of TRX was corrupted?11th May 2008 at 18:40 #52376pixGuest
yes… i don’t know the details, but it is certainly something like this !12th May 2008 at 15:31 #52377Rizwan SaifiGuest
A bundle of Thanx for You
I really appreciate ypur goordination. Thanx once again.
Rizzi12th June 2012 at 19:47 #52378TahseenGuest
Well,Regarding channel failure alarm,I did troubleshooting for almost 60 sites and i never replaved the Hardware.The thing which i did is 1st to check the antenna line by VSWR measurement and even VSWR is fine check please DTF.If u see a small peak which is unsual,It could be connector or jumper,triplexer even antenna.Please check carefully that component.9th June 2017 at 08:03 #52379bieGuest