TCH Drop due to UL Bad Quality

[Ghost78]

Hi;

We did new Frequency plan over dense BSC, but it seems that the result is not as good as we want, we noticed that the contribution of UL Bad Quality in the drop increases after the implementation of this new FP, also the ICM BAND becomes bad. please, if somebody has an idea about the main reason of that, and also how to reduce this amount of drops caused by Bad Quality in UL.

B.R

[electron]

Hi,

It means your FP is not accurate and u have much frequency clash or very tight reuse. Review it again.


Cheers
Hi;

We did new Frequency plan over dense BSC, but it seems that the result is not as good as we want, we noticed that the contribution of UL Bad Quality in the drop increases after the implementation of this new FP, also the ICM BAND becomes bad. please, if somebody has an idea about the main reason of that, and also how to reduce this amount of drops caused by Bad Quality in UL.

B.R

[captain_jejemon]

Check your new freq plan for collision. It is necessary to have DT after the implementation of new Freq.

[Ghost78]

Hi;

thanks for your answers, we did many checks before implementation, for us every thing was OK, but after execution we noticed that the number of drops caused by Bad Quality in DL decreased, in the same time the drops due to Bad quality in UL increases, if we have a non accurate frequency plan, I think we should get a deterioration in DL and UL, am I wrong in this ?, please I need your help.

B.R

[captain_jejemon]

Please do the worst cell first, if there are few cells contribute to high DCR and Bad ICM Band maybe you can work on it. But if the majority of the cells degrade this is a bigger problem.

[captain_jejemon]

How about your handover?

[Ghost78]

Hi;

I have already thought to work on worst cells before, so I'm doing deep investigation on it, and the HO keeps the same trend, I will check it again. thanks to all of you for your support.

B.R

[raghchau]

Hi,

Which equipment vendor you are using..May be I can help you

[Ericsson_RND]

Hi, 1st check cells performance may me there are few weighted cells reflected on performance behavior, if the performance for huge cells is bad after implementing the new Frequency plan you have to revert back to old assign channels.

Also make sure to check BSIC plan, Interference Matrix, can you please let us know which tool has been performed the global plan.

[Inception]

VENDOR ?PLANNING TOOL?BAND ?
did you checked the ICM Band after frequecny implementing ?how much was the weighting ?Did you made the bsic plan before Frequecny plan ?did you audit the nighbors before frequency retuning ?
check your HO KPI for top worst cells that you are sure the reason is bad quality Ul ?
do you have 900 and 1800 together as co-site?

Regards/iNCEPTION

[Ghost78]

Hi,

The vendor is e*******, we used E******* Frequency Optimizer "ex_x-AFP" for planning, our network contain many configurations, cells only 900, cells only 1800, cells 900+1800, and cells 900+1800+1800.
let me give you a summary of our project, we did first BSIC optimization, after that FAS/ICDM and MRR measurement for 3 weeks, IM generation and upgrade, after that based on this IM, distance, HO we removed some neighbors and added other relation, we implement the NB plan 1 week before the FP, we noticed that HO becomes better, on week later, we generate a new Frequency Plan, but after implementation we noticed a degradation on some dense BSCs, and the main reason was Bad Quality in UL, we are actually doing investigation on some cells, if I will get something i'll keep you informed, meanwhile if somebody has something to say, we will be very grateful.

[Inception]

hi
the procedure is looks perferct ,please share with me the BO Report before and after ,and also share the physical and one cna file of your network if you dont mind ,

cheers

[PaleNxtTel]

Dear

Bad Quality in UL usually due to high traffic in tight FP, This is a common issue in such case. what u need to do is to check the worst cells and check the traffic on it and the drop reason if it is Bad Quality in UL so u need to offload the cells or to use clear FR. also if u are using synthesised hopping I recommend to use BB Hopping.
finally try to use 100% AMR\NAMR HR.

please check and let me know.

good luck

Hi,

The vendor is e*******, we used E******* Frequency Optimizer "ex_x-AFP" for planning, our network contain many configurations, cells only 900, cells only 1800, cells 900+1800, and cells 900+1800+1800.
let me give you a summary of our project, we did first BSIC optimization, after that FAS/ICDM and MRR measurement for 3 weeks, IM generation and upgrade, after that based on this IM, distance, HO we removed some neighbors and added other relation, we implement the NB plan 1 week before the FP, we noticed that HO becomes better, on week later, we generate a new Frequency Plan, but after implementation we noticed a degradation on some dense BSCs, and the main reason was Bad Quality in UL, we are actually doing investigation on some cells, if I will get something i'll keep you informed, meanwhile if somebody has something to say, we will be very grateful.

[rubao]

Hi,

In relation to the problem, drops due to UL Qualtiy are usually caused by external interference (military in the EGSM band or UMTS 850 if a network of competitor co-exists with your network). Since you are using E******* equipment please activate RIR/FAS recordings for all the frequencies in your network(but if you want do only for 900 band) and see if there is interfence in the BCCH freqs that are used.

[070057r]

Dear Friend,

If you have overshooting cells , your FP can make bad KPIs of the affected cells by those. Please check the TA of the cells with worst KPIs and tilt down appropriately.
Hope this will help you.

[mobilis]

Hi
witch Hopping you are using SFH (1/1 of 1/3) of BBH of Hybrid ?
1- as it was mentioned before the Uplink interference is caused by External Source so Try to activate the IRC feature for the affected cells this will reduce improve the situation ;
2- Take the Timing Advance MR and Down tilt overshooting cells .

[boob]

im also facing same issue on ZTE equipment

[Ghost78]

I took the 60 worst cells after the FP they had a delta of 6000 drops daily, I re optimized all their RF parameters such as BCCH, MAList, HSN, BSIC, MAIO, but I got the same result, after 3 days of KPIs monitoring, the TCH drop kept the same trend, and the main reason is still due to Bad Quality in UL, really I don't understand why, and I have no idea how to proceed in order to solve this problem.

B.R

[electron]

Hi,

Definitely something is missed my friend and going illogically. I am still recomending you to identify either problem is on new frequency plan or not ! you may revert back the changes in a isolated city or cluster and cross check the result then think about further decision.


Cheers
I took the 60 worst cells after the FP they had a delta of 6000 drops daily, I re optimized all their RF parameters such as BCCH, MAList, HSN, BSIC, MAIO, but I got the same result, after 3 days of KPIs monitoring, the TCH drop kept the same trend, and the main reason is still due to Bad Quality in UL, really I don't understand why, and I have no idea how to proceed in order to solve this problem.

B.R

[daweho]

During the period of measurement report did you factor in planned sites that may have come in after AFP. What is your inter site distance compare to MRR report.