- This topic has 19 replies, 1 voice, and was last updated 10 years, 11 months ago by Pix.
22nd March 2010 at 16:48 #61632campusGuest
please i need an explanation of:
-trx quality pb
-in case of trx quality pb, what does it happen to the calls??
-how to resolve this?
thanks24th March 2010 at 14:38 #61633campusGuest
trx quality pb : when call setup is low, SD drop or TCh drop is high. that means that a the bsc give ressources to the bts but that trx can’t succeed the call (abuses of ressources)
can any one help me more, please..12th April 2010 at 06:50 #61634ManiaGuest
Normally the situation you are describing is of a faulty TRX. Check VSWR, Replace the Equipment if still not resolved check TRE related cables.
It might also be due to severe frequency clashes within cell or with its imidiate neighbour.13th April 2010 at 15:46 #61635campusGuest
hi mania thx a lot but can you explain “frequency clashs”??13th April 2010 at 16:05 #61636BrotherOfTheKingGuest
If a specific cell has bad kpi’s it may have several problems and one of them is trx problem.
So u already found and going well this is the second step now.
What is quality, it is the bit error rate, how many percent of bits had errors or lost. two cases 1 is ul 1 is dl. so if u have stats for uplink and downlink there will be again 4 different scenarios
ul dl both bad quality
ul only bad quality
dl only bad quality
ul dl both good quality
and keep on thinking about this.
which u can fix with changing bcch which can be uplink interference and which is trx problem,
first thing check vswr15th April 2010 at 05:06 #61637ManiaGuest
Frequency clash is when you have same MAIO runing on different radios of same site for 1×1. of same BCCH.
Or the BCCH is same as that of the imidiate neighnbour or in any other SFH or fixed frequency when newarby or same cell is using the same frequency.
Also check combiner port/ Cabinet slot / connecting cables.
Also if more than one TRX of the same cell is having issue check for combiner. it might be faulty26th April 2010 at 16:39 #61638campusGuest
ok mania thinks a lot, but having quality problem with 2 TRXs, without any OMC alarm????
studying quality counters and KPIs, i found no problem with sd drop, tch drop, tch congestion (am working with alcatel)
can you say more please?
thank you27th April 2010 at 04:41 #61639ManiaGuest
Please share the Call Efficiency Inc_HO_Efficiency and DCR_RAd and DCR_HO of these TRXs which is degraded are these degraded TRXs on same combiner / CS04 cable. if so try swapping them with that of another sector to confirm. Also try changing the TRX’s slots in the cabinet that may also get faulty.
Are these TRXs in the inner zone or outer then the cases may be due to other parameter settings.
Also Check if these TRXs are connected to seperate antenna27th April 2010 at 08:19 #61640PixGuest
Why do you say you have a quality problem on TRXs, if you don’t have drops ?
Could you please list the indicators you are using to detect “bad quality” ?
Pix27th April 2010 at 10:36 #61641campusGuest
call eff per trx 91%
ho eff/sector 97%
drop ho/trx 0.5%
drop radio/trx 0.3%
while moving trxs to another sector they work well27th April 2010 at 14:32 #61642campusGuest
there are no drops but call efficiency is low (91%),rate of established calls is low (93%).
pix your question is what i am trying to answer : having 2 trx with bad quality but kpi indicators are ok (sd, tch), hard is ok, trx are ok when swapped to another sector????!!!!
can you help me please?
thank you all.28th April 2010 at 04:52 #61643ManiaGuest
Okies. Now swap the Combiner and the related cables with other secotor .. Two trxs going bad simulatneously indicates a common hardware might be faulty.
If still issue persists on this sector than check the antenna system. If you have a seperate antenna for these TRXs do check that its coverage pattern is same as the other antenna i.e in terms of Azzimuth / Tilts and height.28th April 2010 at 08:40 #61644PixGuest
You should find out which TRX in the BTS has a low efficiency, exactly.
Can you write down the following table (1 line per TRX, 3 columns)?
Number of TCH Allocated / TRX
Allocation Efficiency Rate / TRX
Path Balance / TRX
Pix28th April 2010 at 09:04 #61645campusGuest
they are TRX 3 and 4.
give me a moment to write the table28th April 2010 at 09:26 #61646campusGuest
problem on TRX 3and 4
Number of TCH Allocated / TRX :1511
Allocation Efficiency Rate / TRX : 88%
Path Balance / TRX : 4.95
Number of TCH Allocated / TRX : 1262
Allocation Efficiency Rate / TRX : 88%
Path Balance / TRX : 5.13