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alkesh
2009-05-05, 11:41 PM
What are the effects of Co-BSIC and Co-BCCH on handover?

What is the effect when you have only Co-BSIC? Will handover fail?

Thank you

kais
2009-05-06, 01:05 AM
What are the effects of Co-BSIC and Co-BCCH on handover?

What is the effect when you have only Co-BSIC? Will handover fail?

Thank you

What is the effect when you have only Co-BSIC? Will handover fail? ---- > no effect

What are the effects of Co-BSIC and Co-BCCH on handover -----> HO Fail + rach phantom

venom
2009-05-06, 02:50 AM
What is the effect when you have only Co-BSIC? Will handover fail? ---- > no effect

What are the effects of Co-BSIC and Co-BCCH on handover -----> HO Fail + rach phantom

As far as i know, in SIEMENS co-bcch and co-bsic can not handover because the database will not take the values. It will give error !!!

Even in SIEMENS, you can not provide SAME BCCH with different BSIC as a NON-TGT NEIGHBOUR !

electron
2009-05-06, 02:55 AM
Ms will be confused!!

radenmohawk
2009-05-07, 04:49 PM
What is the effect when you have only Co-BSIC? Will handover fail? ---- > no effect

What are the effects of Co-BSIC and Co-BCCH on handover -----> HO Fail + rach phantom

Yeah... that's right.
Co-BSIC and Co-BCCH --> impact to increase HO-Failure and Low RACH success rate.

venom
2009-05-07, 09:54 PM
Yeah... that's right.
Co-BSIC and Co-BCCH --> impact to increase HO-Failure and Low RACH success rate.

Co-BCCH and Co-BSIC can not be neighbor then how can u have HO Failures?

ghassen
2009-05-07, 11:48 PM
As far as i know, in SIEMENS co-bcch and co-bsic can not handover because the database will not take the values. It will give error !!!

Even in SIEMENS, you can not provide SAME BCCH with different BSIC as a NON-TGT NEIGHBOUR !
it's right when you are aplying these parameter and you submit the LMT wil not execute this MML command and will prompt you that this is not alowed freq or value this is like a internal check in siemens database to avoid confusing situation
please for the other experts on other vendor make comment about your equipment to know on these mismatch impact

zaebolll
2009-05-08, 12:13 AM
NSN BSC also doesnt allow Co BCCH-BSIC cases for nbr cells,

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

BR\

radenmohawk
2009-05-09, 12:34 AM
Co-BCCH and Co-BSIC can not be neighbor then how can u have HO Failures?

Yeah.. I mean in the case if those cells not created as neighbor but have same BCCH and BSIC.. :)

venom
2009-05-09, 02:19 AM
Yeah.. I mean in the case if those cells not created as neighbor but have same BCCH and BSIC.. :)

If the cells are not created as neighbors then there is no HANDOVER !!!

The answer to his query is very simple, Co-BCCH and Co-BSIC can not be neighbor, HO is impossible in it that is why the BSS System can not take the values and internal check gives u an error when u try to make Co-BCCH and Co-BSIC as neighbors.

In Siemens, Co-BCCH can not be a neighbor, even if the BSICs are different it will not take the Co-BCCH as a neighbor.

codebox
2009-07-19, 03:18 AM
Hi,

Of course Co BCCH-BSIC can not be added as neighbors, i.e source and destination cant have same BCCH-BSIC combination,
but,
Same source cell A can have two neighbors B and C with both B &C having same BCCH-BSIC combination. This will effect Out HOSR of A and Inc HOSR of B and C. (plus phantom RACH)

In addition, even if one of the cells B or C is added as a neighbor with A, even then there will be HO issues from A=>B or A=>C bcz interference or decoding prob will still be there.

correct me if i am wrong.

BR
LCC Level2

kais
2009-07-19, 05:44 AM
:victory: very good


Hi,

Of course Co BCCH-BSIC can not be added as neighbors, i.e source and destination cant have same BCCH-BSIC combination,
but,
Same source cell A can have two neighbors B and C with both B &C having same BCCH-BSIC combination. This will effect Out HOSR of A and Inc HOSR of B and C. (plus phantom RACH)

In addition, even if one of the cells B or C is added as a neighbor with A, even then there will be HO issues from A=>B or A=>C bcz interference or decoding prob will still be there.

correct me if i am wrong.

BR
LCC Level2

rajmeena06
2011-04-23, 03:08 PM
I have doubt genious ,
In my network i found co-BSIC/BCCH But they are not in neighbour list of each other and minimum distance between them is approx 3 Km.so in these case these will effect my network perfomance ,Pl clear.

poncho
2011-04-23, 05:12 PM
Co-BSIC/co-BCCH if on neighbour sites (neighbours as in geographical location not definition because sometimes neighbours with co-BSIC/co-BCCH are not defined yet they affect HOSR performance) will affect handover fail and you will even notice it in drive-tests. RACH fail will also be high on target cell. But if the sites are not gegraphical neighbours and not overshooting, co-BSIC/co-BCCH situations don't really affect performance. So due to tight frequency plans in some situations which prevent co-BCCH situations from being avoided you can avoid co-BSIC by using all the range of NCC (0-7) to diversify the BSIC. I hope this helps. Let me know.

What are the effects of Co-BSIC and Co-BCCH on handover?

What is the effect when you have only Co-BSIC? Will handover fail?

Thank you

didemir
2011-04-25, 05:53 PM
if the cells are under same bsc (meaning tey are close to each other) , you cannot use same bsic-bcch couple.. we use at least 10km border to use same couple.. same couples make bsc confused to choose which cell will be the next as nei. --> certain drop

same bsic with different bcch --> no drop