- This topic has 7 replies, 1 voice, and was last updated 14 years, 9 months ago by MKT.
13th February 2008 at 14:52 #50989BilalGuest
Can anybody explain how BSIC planning can impact Random Access Success Rate?18th February 2008 at 18:02 #50990ARPANGuest
Try to use co-channel co-bsic as far as possible and in opposite directions.. it will reduce the probability of random access failure rate…18th February 2008 at 18:43 #50991PixGuest
The BSIC of two cells should be different ONLY if they use the same BCCH.
The TSC shall be equal to the BSIC.
Finally, the impact of co BSIC and co BCCH : SDCCH Assignment failures (and or Random Access failures), HO failures, and possibly wrong decoding of TCH (interference) due to same TSC.
One RACH sent to one cell will also be decoded to the other cells. Both cells will send an Immediate assignment, but only one will receive an answer from MS. The other one will count this as a sdcch assignment failure due to poor radio (alcatel systems).
Pix19th February 2008 at 06:19 #50992BILALGuest
So if we have 15 BCCHs and 64 BSICs, having unique combination of BCCH and BSIC for every cell in an area can never be problem. Am i right?19th February 2008 at 08:44 #50993PixGuest
You don’t have 64 BSIC’s, because BSIC = NCC & BCC. The NCC is the network country code, which was allocated to your operator by the telecom regulation agency. Normally, you have only 1 or 2 NCC’s (right ?). Then you have only 8 BCC’s to play around with (from 0 … 7)
But still : this is plenty enough to avoid problem.20th February 2008 at 05:29 #50994BilalGuest
What is the point in having different NCC’s for different networks in a country? As we know that every operator has different band of frequencies so there is no chance of co-BCCH-BSIC across the operators. Anyways in our country every operator is using all available NCC’s and BCC’s i.e. 0-720th February 2008 at 10:15 #50995PixGuest
yes, you’re right… i don’t know why the NCC should be unique, it’s something i took for granted, but your explanation makes much more sense.20th February 2008 at 10:45 #50996MKTGuest
In countries like India the license is given on state basis, not a single
license to operate throughout the country. One license area normally corresponds to one state.Hence in neighboring states the same operator
(same BCCH frequencies)situation can
exits. This is common at state borders.