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johnisalive
2014-02-28, 01:06 AM
I have a remote site on a highway, that hands off perfectly to a different RNC. RF condition has been improved but there is a high DCR.
Neighbors have been reviewed okay. The signal is being dragged a little bit to the other side, but I do not want to downtilt just yet because it will limit the coverage in some areas of the highway.
I want to see if I can do something else.
I added some bias to make the other site look better.
Spectrum Analyzer doesn't show interference, and the only guess is external interference on the downlink which will be tedeous to do.
Any other ideas?

electron
2014-02-28, 02:09 AM
Hi,


Most probably drops are coming by fast moving users in high way try to change individualoffset(In E/// system ) on one of the cells( preferably on target sell) your problem will be solved.


Cheers
I have a remote site on a highway, that hands off perfectly to a different RNC. RF condition has been improved but there is a high DCR.
Neighbors have been reviewed okay. The signal is being dragged a little bit to the other side, but I do not want to downtilt just yet because it will limit the coverage in some areas of the highway.
I want to see if I can do something else.
I added some bias to make the other site look better.
Spectrum Analyzer doesn't show interference, and the only guess is external interference on the downlink which will be tedeous to do.
Any other ideas?

tsiz
2014-02-28, 03:03 AM
I agree with Electron. Have you tried individualoffset for a faster handover? Also, have you checked your external UTRAN relations, maybe you are missing some overshooter that might need to be added?

amadeo
2014-02-28, 03:35 AM
HI John,
Mostlikely it is late HO. For voice or R99 data, you can increase the maximum power on connected mode. In NSN the parameter is CPICHTOREFRABOFFSETT. You can put them into 2 or 4 dB greater than CPICH.
Other thing you can check is your SHO OH, if the value is too low, that means you have coverage gap. Find it out and uptilt or increase CPICH (if no DL power capacity issue).
The final trick is to increase your T313 so that it will give you more time to HO instead of drop your call.

Hope it will help.

cheers


I have a remote site on a highway, that hands off perfectly to a different RNC. RF condition has been improved but there is a high DCR.
Neighbors have been reviewed okay. The signal is being dragged a little bit to the other side, but I do not want to downtilt just yet because it will limit the coverage in some areas of the highway.
I want to see if I can do something else.
I added some bias to make the other site look better.
Spectrum Analyzer doesn't show interference, and the only guess is external interference on the downlink which will be tedeous to do.
Any other ideas?