UL Quality Problem

[Hacen]

Hi experts,
Can you expalin me how can resolve the problem of call drop due to Quality (UL Quality)

Think you very much

[magno22]

Firstly you need to check interference and congetion.

[plannerguy]

Hi

is it 3g or 2g?
g
Reagrds
plannerguy

R

[Hacen]

Hi
it is 2G Alcatel
think you

[Hacen]

Hi magno22
Can you explain me How can congestion influence the quality
think you very much

[usama0795]

Congestion can effect quality as if features like Directed Retry or congesiton based HOs are allowed its going to increase the footprint of neighboring cell on which call is being thrown as best cell would be serving cell w.r.t to level right now but call would be thrown on some neighbor with approx 2dB level less then serving cell depends upon parametric settings.....resulting in increase in noise floor of the network....initially considering this sceario directed retry and congestion based features were activated on per cell basis but with ever increasing traffic most networks have enabled these faetures on every cell......

[fantominox]

Hi Hacen,
- first of all you need to identify character of interference: internal or external.
To find external you should check interference level not only in most interfered cell but also in adjacent cells. I don't know Alcatel BSS but at other vendors you can see statistics concerning UL interference measured for idle timeslots. Also check HO distribution in cells. If adjacent cell are interfered more or less too, it can be external interference. You can perform some measurement in field with spectrum analyser too. If it's external source occurs, find it and eliminate.


If you are sure it's not external interference than:
- check if all TRX's and RBS combiners ( generally HW ) are OK,
- check frequency plan
if hopping: check MAL and MAIO,
- switch on DTX (DL/UL),
- switch on POWER CONTROL - it decreases interference,
- try to limit number of TRX with packet transmission if you implemented EDGE/GPRS on all TRXs, Power Control doesn't work for EDGE/GPRS. Try packet transmission on BCCH only,
- optimize tilts,
- implement AMR and then push more traffic to AMR HR - voice will be sent every second frame decreasing interference.
Additionaly AMR allows agressive Power Control settings for AMR codecs.


BR
Fantominox.


If it' s helpful plz ad R.

[sidali1783]

Hi Hacen
UL Quality is generally caused by 2 major problems
1- exteral intreferences
2- overshooting problem
there are other problems like HW problem but you need to check the above problems
brs

[nandi_saikat1]

Hi, We have almost 90% NW utlization. Frequency plan has been shared as output of AFP Netmax tool with ZTE system. The NW is of ZTE 2G only. Can you suggest for any parameters which can help to improve UL/DL Quality?

[khurrambilal01]

Make your power control more aggressive (Reduce the frequency of POC, N & P values should be 1/1, Thresholds should be lowered for DL/UL POC like -90/-88 to -86/-84 etc to further reduce the interference).
I made power control more aggressive and the result is improved KPIs with lesser DL/UL interference.

[Syed Fahad]

Dear,

Considering the Volatile Nature Alcatel BSS Product, we need to check the Diversity and Delta Path loss per TRX for the top culprit cells.
In Alcatel, Congestion has direct impact on DCR and HSR incase Directed Retry, Forced Directed Retry, General Capture HO's and Traffic HO's are enabled on a very large scale.
In cities, Fine tuning, relaxing PC windows for UL and DL gives fruitful results by imroving UL/DL Qualty HO's.
Bad Redesign has direct Impact on Subsciber Percieved UL / DL Quality

[nandi_saikat1]

Hi Sir, Physical optimization completed. It's Jamshedpur NW in India/Bihar. AMSL variation is very high. It's ZTE 2G NW.
Presently, POC for UL lev has been define as -78 to -86 and for DL -75 to -85 with P/N as 1/2; POC quality has been defined as 0 to 2 for UL & DL with1/2 criteria;HO will trigger at -95 lev and Quality as 2 for UL & DL with 2/3 criteria to be fulfilled. -90 is the lev to be a candidate for HO (rxlevmin); With this settings my UL quality is 96.8%. Huge pressure is to improve the same upto 97.5%. Please suggest.
Initially Rxlevmin was -95; after modifying the same to -90,CDR & HOSR improved at this NW.

[nandi_saikat1]

Hi Khurrambila,

Please suggest.

[Shakeel_15]

Check

Uplink Interference - Idle TS Stats.

Check faulty hardware.

Also check interference boundary settings and average level of non decoded rach.

BR


Hi experts,
Can you expalin me how can resolve the problem of call drop due to Quality (UL Quality)

Think you very much