RRC connection access,Registration Sucess Rate Degraded in 3G Cell

[dext]

Hi Experts

I have a small query in our Live ZTE 3G network of a dense city during rollout a site came on air, One of the sectors is having RRC Connection Est Rate degraded to 93% , when investigated it is found that the RRC Connection access Registration success rate is degraded and we have relatively high number ofrepeated RRC connection requests for registration.

What might be causing this ? , and what is the algo for the UE registration, what factors should i be checking ? is there any further investigation possible ?

Regards
Dext.

[yafawi79]

Dear dext:
One of the possible reasons is that this cell might be at the border between two RNCs, if yes, number of registration due to LAC update when UEs move from one RNC to the other RNC will be high causing also high number of Uu no reply due to interference kindly confirm

[dext]

Dear dext: One of the possible reasons is that this cell might be at the border between two RNCs, if yes, number of registration due to LAC update when UEs move from one RNC to the other RNC will be high causing also high number of Uu no reply due to interference kindly confirm

Thank you , Yes that is the case the cell is on the RNC border, so now is there any way to reduce this registration and improve the RRC http://www.finetopix.net/images/smil...used.pngBRDext.

[yafawi79]

Yes; IN THIS case You can tune idleqoffset1sn and idleqoffset2sn to higher value say 5 or 10 dB on the neighbor cells of the other RNC only. The idea is to reduce the number of cell reselection from the neighbor cells in the source RNC towards the cell which has the problem thus less number of UEs will reselect and less regestration will be. Based on the ranking creteria. ALSO you check if these cells are overshooting and try to downtilt its antenna to reduce the footprint inside the target RNC.