- This topic has 36 replies, 1 voice, and was last updated 12 years, 11 months ago by Pix.
8th October 2008 at 14:49 #54050Sami YassinGuest
with Same (BCCH,BSIC)couple, SDCCH RF access failure is impacted badly.
What abaout adjacent cells with same BCCH and adjacent BSIC or Same BSIC and adjacent BCCH?
Is it effect SDCCH RF access also?
I realy appreciate if any one help me with these.9th October 2008 at 11:57 #54051pixGuest
same BCCH or adjacent BCCH will lead to very poor RF performances, whatever the BSIC value. co bcch and adj bcch should be located as far away as possible from each other.
(adj BCCH, same BSIC) will not lead to “phantom” allocation like you are seeing with (same bcch, same bsic). Because the frequencies are different.
(same BCCH, adj BSIC) might lead to some problems, because actually the BSIC is not acting as a filter. The two BCCH will understand each others Channel Requests. I might be wrong though, let’s say I’m 80% sure about that.
Pix9th October 2008 at 15:35 #54052Sami Yassin AhmedGuest
Many Thanks Pix..
Plz do me favor and explain what you meen by (because actually the BSIC is not acting as a filter)..
Sami12th October 2008 at 17:36 #54053pixGuest
what i meant was that a Channel Request message does not contain any information about the BSIC. When a MS sends a Channel Request on a certain frequency, all cells using this frequency as a BCCH can hear and decode it.
They will understand it as a valid Channel Request, whichever their BSIC.
The only constraint is that it’s on their BCCH frequency, and it reaches the BTS during the TS0. If it arrives after or before, it’s going to interfere another timeslot of the TRX.
Pix8th February 2009 at 06:23 #54054Masud Parv ezGuest
could you explain me why we using BSIC. Is this possible with out BSIC the MS can send a channel request?8th February 2009 at 08:23 #54055PixGuest
The BSIC is an identifier of the cell, so that MS can distinguish between two cells using the same frequencies.
About the channel request, it’s a little weird. A cell is always tagged with a certain a BSIC, so a MS is always going to send a channel request in a cell which is broadcasting a BSIC. Your situation is impossible 🙂
If a cell doesn’t have a BSIC, the world would come to an end.7th December 2009 at 11:16 #54056BalajiprasadGuest
I got single digit BSIC value in field.It is considerable or not?How to convert this value?How to representation this value?Ex:14 or 1,47th December 2009 at 12:03 #54057AliAsgherGuest
Just to clarify, For cells with Same BCCH, and Same BCC part of BSIC (BSIC = NCC, BCC) the KPIs will still degrade.
This is due to the fact that BCC part is the one which is used in Access Burst. (May cause Phantom rach requests too. These requests are there as Access burst is same for Handover, RACH attempt and GPRS).
Also, Adjacent BSIC does not pose ANY problem. So Pix should be 100% sure about it 🙂 This is due to the fact that the actual sequences corresponding to the different BSICs are orthogonal.
I have got multiple 1.5 volt battery cells that does not have a BSIC, but my world hasn’t ended 🙂
Regards,7th December 2009 at 12:09 #54058BalajiprasadGuest
Sir,I got BSIC value in my netmonitor phone(Model LG KP100).But is is single digit.Ex:8.But we have to receive NCC+BCC.Why it is happening?It is considerable or not?7th December 2009 at 12:30 #54059PixGuest
And yes, you are right about adj BSIC. But I was talking as :
(same BCCH, adj BSIC)
So you see, one year ago, I said that the BSIC info is not contained into the channel request. However, that is not true.. The BSIC is contained in the training sequence code located in the middle of the Access Burst. So it does act as a filter.
Conclusion : Pix is improving with time.
Like a good french wine.
Except Pix doesn’t make people sick in the morning….
🙂7th December 2009 at 12:32 #54060PixGuest
It is probable that your NCC = 0. You can check that in one of the SI message the MS receives from the BCCH.
0 = 0/0
1 = 0/1
2 = 0/2
7 = 0/7
8 = 1/0
9 = 1/1
10 = 1/2
You can convert easily by using the microsoft Scientific calculator (write in decimal and click on “hex” button)7th December 2009 at 12:57 #54061BijoyGuest
Tell me when can I have a dinner with you? Need to quench my thirst with “Old French Wine” :-))7th December 2009 at 13:28 #54062PixGuest
Your post is very open to ambiguous interpretations…
I’ll just assume you want to get drunk :))8th December 2009 at 07:54 #54063AliAsgherGuest
Regarding “ambiguous interpretations”, I am shocked how telecom experts ask each other for dinner 🙂
Well actually, I think still there might be room for improvement as whole BSIC is NOT contained in the Access burst. It is only the BCC part.
Just let me know when the French wine becomes strong enough to start making people sick 🙂8th December 2009 at 08:32 #54064BijoyGuest
I asked Pix for dinner as now he is “old french wine” & I dont want to miss the oppurtunity to taste old french wine.
Interpretaions are individual’s intention dependent,i’ve no controll on that.:-)
Maybe I can restrict myself for posting such (freindly) messages further