- This topic has 7 replies, 1 voice, and was last updated 16 years, 8 months ago by Tomar.
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7th August 2007 at 12:24 #48626syed Adil AliGuest
the situation of the cell:
1) there is no congestion on the cell.
7th August 2007 at 13:06 #48627vivekGuesthi,
I wud also like to know about this problem as i am also facing similar problem in few cells.
I have been able to resolve most of the cell but it still perists in one cell.
For the other solved cells I checked out the frequency issue & resolved it.
But for one cell I am nt able to solve this problem.
kindly help.7th August 2007 at 13:08 #48628vivekGuesthi Ali,
U need to check the frequency plan for this.
As i also faced similar problem & I was able to sort it out just by improving my freq. plan.
Some freq (adjacent /co) must be hitting…
check it out..
Also get the hardware checked..8th August 2007 at 04:21 #48629Syed AdilGuestHi vivek,
Thanks for your response.
There is no ajacent and co freq. in this cell and the inter site distance between this site is aprox. 2.5 km and also this site belongs to the remote city consist of 11 cell dual band cells.
If you talking about hardware some times got lapd alarms.8th August 2007 at 07:59 #48630pixGuesti faced such a problem as well… got to change the BTS hardware in order to solve the problem…
8th August 2007 at 08:31 #48631TomarGuestHi All,
I have same experiences. If there is no BCCH-BSIC conflict, than check, if there is some HW problem. From cell trace compare UL and DL measurement – path balance. From statistic: there was a lot HO failure from two neighbors. There was difference between UL and DL 15 dB – wrong TMA. The next reason could be also wrong setting of parameters –ping pong HO. It is mostly on dual-band cels.
BR
Tomar8th August 2007 at 08:43 #48632patrickGuestwhen handover failure, what’s can you tcheck first and which parametercause bad handover
8th August 2007 at 13:37 #48633TomarGuestHi Patrick,
My suggestion are:
To check difference between Attempt without HO and Seizures without HO.
To check distributions of measurement on each TRX in DL and UL direction.
To check Idle band (somebody could transmit in your frequency band or any of your NB site)
Very important is just the time, on when the statistic was broken.
To check reason for HO. If necessary than we could run Cell Trace on the problematic cell and also on the neighbor cell. From measurement we could observe, what is wrong (bad level or bad quality).From my experiences, if you set HO margin to low in one direction and to back (0 dB) there are lot of ping pong HO. We have to set some limit of repetition of PWRBGT HO.
If you set HO RXLEV access to low (-102 dBm) there will be a lot of unsuccessful HO.
Check settings of frequency plan (BCCH, TCH, HSN, MAIO). I saw sometimes that on the site with HSN=XX (synchronized manager) was MAIO=0 on two cells.
And many others.
BR
Tomar -
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