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zeldalcl
2011-10-26, 10:26 AM
Hi Everybody!
The pilot polution coverage are big problem in Coverages. Who have neighther any idea to detect Plot Polution areas by MRR or STS.... nor have experence about this please share me.
Any body, who known which can be detect pilot problem. Plz tell me.
Thanks
BRs!

vivero
2011-10-26, 03:46 PM
Hi, please read 2 documents. They will instruct you how to detect pilot pollution by Actix.
Thanks!

vivero
2011-10-26, 03:47 PM
And this is the next one.
Thanks!

jan74
2011-10-26, 05:33 PM
Hi Everybody!
The pilot polution coverage are big problem in Coverages. Who have neighther any idea to detect Plot Polution areas by MRR or STS.... nor have experence about this please share me.
Any body, who known which can be detect pilot problem. Plz tell me.
Thanks
BRs!

What does MRR and STS stand for?

zeldalcl
2011-10-27, 12:34 PM
Hi all!
I would like to thanks to every body in thread.
I known The Actix Toll can detect The pilot pollution problem. But which need dritest log. So we can not driving test any time, any where then we want to detect by another way.

BRs!

liukang
2011-10-27, 02:05 PM
Hi all!
I would like to thanks to every body in thread.
I known The Actix Toll can detect The pilot pollution problem. But which need dritest log. So we can not driving test any time, any where then we want to detect by another way.

BRs!
Pilot Pollution you need have drivertest logfile to detect that problem. After RF planning we can reduce pilot pollution, but pilot pollution occur at some area if you have not logfile to analyze you can't know pilot pollution (can't know from MSC, RNC,...).
If you working with CDMA system, i know Lucent's RF SPAT3g can detect which site affect pilot pollution but i never use it.

zeldalcl
2011-10-28, 02:47 PM
Hi everybody!
What do u think about the size of Active Set, Normally we design 3link in activeset . While We always face with Pilot Pollution.Why we can not increase the link that can be added to active set. Everybody who have any information about the size of AS please share me.

BRs!

D33T0X
2011-10-28, 03:10 PM
Hi,

Increasing the Active Set Size was not helping 2 years ago as the phones didn't support to be connected to more than 3 cells in the same time (eventhough in RNC I declared ASS=6). However, you can have a look at your stats, identify the areas in which you have most RF drops and then drive test these areas, that's my advice.

cwintery
2011-10-28, 05:25 PM
Which vendor do you work? If it's NSN 3G, you can.
I have worked with NSN 3G. There are some counters can count Ec/No distribution of intra-frequency neighbors.
Use them, you can detect and optimize Pilot pollution.
With the other vendors, such as ALU, E*******, Huawei..., I don't have information about that.
Anyone can share your experience about those vendors?
Thanks!

D33T0X
2011-10-28, 06:18 PM
Huawei - you have the same, can identify the cells with low Ec/No. But low Ec/No can be caused by other factors than pilot pollution. You don't get away without drive test - you need to see why the Ec/No is low.

Mohamed_yehia
2011-10-30, 03:22 PM
Dears regarding huawei how can we get low ec/no cells without dt?

keanchan
2011-10-30, 03:45 PM
For Huawei, CHR would be a good data source to detect pilot pollution as it collect measurements from all user.

Going through the measurement reports, you would be able to identify cell with pilot pollution problem. Cell with high number of Soft handover Replacement candidates are usually experiencing the pilot pollution.

stilloboy
2011-10-30, 05:10 PM
Hi all!
I would like to thanks to every body in thread.
I known The Actix Toll can detect The pilot pollution problem. But which need dritest log. So we can not driving test any time, any where then we want to detect by another way.

BRs!

There are 2 ways actually to detect any problem in a wireless network. By using OSS visibility and by analyzing drive-test logfiles. The latter usually is the only way if you've confirmed from the OSS that the issue is radio-related (i.e., radio environment is poor). The problem you've highlighted, i.e., that of pilot pollution, is a radio-related problem and the best way (and probably the only way) is through a drive-test around the affected cluster(s).

liukang
2011-10-30, 07:43 PM
There are 2 ways actually to detect any problem in a wireless network. By using OSS visibility and by analyzing drive-test logfiles. The latter usually is the only way if you've confirmed from the OSS that the issue is radio-related (i.e., radio environment is poor). The problem you've highlighted, i.e., that of pilot pollution, is a radio-related problem and the best way (and probably the only way) is through a drive-test around the affected cluster(s).
From OSS we know cell affect to Pilot Pollution but we can't know the way to decrease PP problem (decrease PP problem we need adjust Azimuth, tilt, and maybe Power)

BR!

keanchan
2011-10-30, 11:44 PM
From OSS we know cell affect to Pilot Pollution but we can't know the way to decrease PP problem (decrease PP problem we need adjust Azimuth, tilt, and maybe Power)

BR!


From the OSS Traffic Measurement like Huawei CHR and E******* GPEH, you will get the measurement report and SHO details including the propagation delay from the cell. With proper tools like Huawei Nastar or Xeus Pro from my company Aexio, you can identify and resolve the pilot pollution problem.

My optimization skill is quite limited but here are what I will do with those information.

1. Is the affected cell are serving too far/overshooting which leads to high Pilot Pollution? If yes, increase electrical tilt to reduce the coverage
2. Are there any missing neighbour that cause the pollution? If yes, add the neighbour relation.
3. If none of above, which cell are causing the pollution to the affected cells. If they are neighbour, a large amount of Soft handover replacement shall occur. Are they overshooting? Yes yes, tilt/reduce power etc.

I have attached a snapshot from the Xeus Pro showing the polluter.

Hope this helps

zeezzoo
2011-10-31, 05:30 AM
for huawei you can detect pilot pollution by Genex Nastar tool (which uses CHR files).

the criteria used in Nastar is : for a givin user if there was two consecutive "1C" HO events within 5 seconds ==> then this is pilot pollution .

also you can use the counters of Ec/No & CQI (NodeB Counters) . Also the most important things are the counters of "1A/1C" HO events & soft HO Overhead KPI .

hope this helps

zeezzoo
2011-10-31, 06:08 AM
From the OSS Traffic Measurement like Huawei CHR and E******* GPEH, you will get the measurement report and SHO details including the propagation delay from the cell. With proper tools like Huawei Nastar or Xeus Pro from my company Aexio, you can identify and resolve the pilot pollution problem.

My optimization skill is quite limited but here are what I will do with those information.

1. Is the affected cell are serving too far/overshooting which leads to high Pilot Pollution? If yes, increase electrical tilt to reduce the coverage
2. Are there any missing neighbour that cause the pollution? If yes, add the neighbour relation.
3. If none of above, which cell are causing the pollution to the affected cells. If they are neighbour, a large amount of Soft handover replacement shall occur. Are they overshooting? Yes yes, tilt/reduce power etc.

I have attached a snapshot from the Xeus Pro showing the polluter.

Hope this helps


I'm a little confused .
this tool is it for free or only 30 days demo ? cause in the web site i saw two different download pages each one say so .

zee86
2011-11-25, 08:26 PM
GPEH trace in E******* is the best trace but we need to convert it in readable form can some share how we can do this

melkaiy
2011-11-25, 09:29 PM
because the active set window is only 3 active sets and greater than that is already a pilot pollution. You cab check the pp% in the post-process analysis tool. There should be an overhead i mean considered threshold of pipolt pollution you can the percentage. By the way this is the formula for pp percentage:
pp% = total ec/io counts/ total piot pollution counts. consider a pilot polluiotn percentage per area with greater than 40% if there is no threshold set.

please add reps if this one hepls.. if ypu like it :)

vns1_bk
2011-12-15, 12:17 PM
after driving test you can use actix software or assistant software for detect pilot polution.