- This topic has 38 replies, 1 voice, and was last updated 4 years, 1 month ago by Abdullah.
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3rd March 2010 at 06:34 #61271Karan SinghGuest
Hi,
The equipment is ZTE, Traffic load is quite low, around 2000 BTS scattered all over there are a few coverage holes.
Setting :
MFRMS :4
AGBLK : 1
T3113 : 8s
T3212 : 2 hrs
Implicit detach timer : 6 hrs
TX Int. : 12
SD Assign success rate : 89%
No SD Blocking! i.e. arn 0.25%
Any suggestions ??3rd March 2010 at 12:50 #61272PixGuestDid you activate the AGCH Preemption ? Because here there is only 1 AGCH block reserved for immediate assignment, statically. So unless you activated the dynamic AGCH preemption, it sounds to little.
Try increase AGBLK to 4.
3rd March 2010 at 21:57 #61273RexGuestHi,
And what about T3212 timer. Try increasing to 3 hrs or 4 hrs.
Regards,
Rex4th March 2010 at 14:25 #61274safarGuesthi pix,
By increasing agcl blk value will it help to improve pch ?
Or anothet question if i have high sd blocking and agcl blk is 1 then in this case by increasing agcl blk will help to reduce sd blking?
5th March 2010 at 13:28 #61275Karan SinghGuestHey thanks for the response guys..
@Pix : AGCH is hardly an issue..no SD Blocking as i mentioned. Well we are implementing the changes tonight. Hope bringing down the Implicit detach timer from 24 hrs to 6 hrs would help, besides, MFRMS is changed to 3. Got my fingers crossed.
@Rex : T3212 is set to 2 hrs..no sd blocking @ all..can sure try n change it to 4 hrs though..:)5th March 2010 at 15:11 #61276pixGuestKaran Singh
The AGCH congestion is different from the SDCCH congestion, or SDCCH blocking. We are talking about 2 different channels !
It is something that is usually overlooked in the KPIs (except for erlang.com addicts 🙂 )
your SDCCH assignment success rate is low, and it COULD be caused by AGCH blocking.
If AGCH block reserved = 1 and there is no dynamic preemption, then you surely suffer from AGCH congestion.
Now, you actually don’t have a problem, 89% is totally acceptable, especially in low-traffic cells in rural areas. Lots of Ghost RACH, some coverage holes. Some RACH Requests might reach the BTS, but the answer from BTS to MS is never received by MS. That counts as a SDCCH assign failure.
You can reduce it by increasing your RXLEV ACCESS MIN from -110dBm to -100dBm, for example (just to check the impact).cheers
pix5th March 2010 at 20:35 #61277Karan SinghGuestPix..that was quite enlightening ;)..sure AGCH & SD are different channels. I’d suggest..read between the lines..less traffic..less AG load ..less sd load..hope u understand..moreover..when talking about improving PSR, it is irrelevant to advise to increase AGBLK to 4 which in turn decreases no.of PCH blocks (I would not mind it though in this case as traffic is low). Besides, before reducing the RXLev acc min , i’d suggest take a look @ link imbalance report as effective radius might be reduced unnecessirily, adding TMAs for better u/l is a good option too.
6th March 2010 at 20:15 #61278pixGuestKaran,
When you ask a question on this forum, you can’t just shoot down the answers given.
Especially mine !! 😀
By the way, what is your Paging Success Rate ? This could be a valuable info…
Cheers
pix8th March 2010 at 07:30 #61279Karan SinghGuestI agree..:) ..Hey…PSR which was around 79.9 % has risen to 87.01 % over last 2 days, though still not great I believe it is optimum as sites are scattered with lot of coverage holes..i guess changing detach timer to 6 hrs & T3113 to 8 s from 6s brought it up by about 4- 4.5 % rest of the improvement is a result of params like MFRMS/TX Int etc.
14th March 2010 at 06:22 #61280MadhurGuestHi
How can we improve the PSR ?
Pl let me know if any parameter is required for the same…
Equipment is Huawei…
16th March 2010 at 12:30 #61281BasharatGuestCan you please share the calculation method of MFRMS/TX Int to improve PSR?
we have done many steps to improve PSR like, MfRMS 3 from 5, reduce the T3212 timer from 2hrs to 1 hr,increase First paging responce timer from 6s to 7s but we are enable to find required results.
current Parameter settings
TX Int.: 2
MFRMS :4
AGBLK : 2
No SD blocking
Vendor: ZTEAny suggestion
16th March 2010 at 12:38 #61282BasharatGuestI havn’t find below timer in ZTE system
T3113 : 8s
Implicit detach timer : 6 hrscan you tell the relevant timer against them?
17th March 2010 at 17:26 #61283safarGuestHi,
i want to know abt poor paging is also due to edge,gprs.
because in our network eric when downloadng is going on and voice call will come then out of 10 case in two case paging is discarded is it?
and somebudy knows abt GS interface? its betwwen msc and sgsn. i heard that by keeping gs interface we can improve pch sucess ratio?
13th April 2010 at 07:27 #61284RexGuestHi,
what’s the role of parameter AG_PREMPT_PCH (Alcatel Rel B9). Will it improve paging success rate, paging congestion?
Another question, how to know which cell is more paging congested? Any indicator available in RNO (I can see just paging load but not discards and congestion) or other way to calculate discard or congestion.
Regards,
Rex13th April 2010 at 10:20 #61285Karan SinghGuest@ Basharat : Hi, Its important to realize the traffic in the LAC. Check if its correctly dimensioned. Cover the coverage holes too. Yes there is a mechanism of calculating MFRMS, can share it offline, its a doc. Anyway, pls understand that for high traffic environment i.e. utilization of LAC is >75%, use higher value of MFRMS like 5 or 6(depending upon traffic). Tell me what is the Implicit detach timer value for the network?
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