- This topic has 12 replies, 1 voice, and was last updated 10 years, 7 months ago by
.
-
Posts
-
Hi All,
Can anyone help me understanding How an abis interface is formed b/w BTS and BSC? Is it a single connection from TRX to BSC or BTS to BSC? How does the channel allocation of OMUSIG and TRXSIG is done? What is the autoconfiguration of abis means?
Vimal,
one Abis interface is the link between one BTS and its BSC.
several BTS can share the same link (they share the capacity of the link).
Allocation of the OMUSIG and TRXSIG is usually manually performed at the OMC-R, but it could also be done automatically (it’s really simple).
Autoconfig is certainly a proprietary feature of the vendor, i don’t know what it is.
Hi Pix,
Thanks for the reply.. But the statement “several BTS can share the same link (they share the capacity of the link).” is not clear to me. How one physical link b/w BTS and BSC can be shared by other BTS? Can you detail it. Thanks.
can anyone tell me how to implement autoconnection feature between BTS AND BSC so that scf file can be uploaded.plz reply asap.i will be highly obliged
Depending on your BTS type, there are different configurations, e.g. star, multi-drop and loop configurations.
You can go from the BSC to the first BTS, then from that BTS to the next BTS, and from that BTS yet again to another BTS. This topology might be cheaper since you dont need as many E1 line cards at the BSC, and the lenght of the E1 lines might be shorter between two BTS rather than going all the way to the BSC from every BTS.
Regarding ‘how it is formed’: It’s the same like on any ISDN link (Q.921). Each BTS has one OML link which is established using a fixed TEI establishment procedure. Every TRX has one more link, each with their own TEI.
Thanks for ur reply.I want to know that whether AutoConnection Feature has been implemented ever.That is upload\download SCF from BSC to BTS and vice cersa.
where is the signaling of PCM 64kbps speech channels in E1 as speech channels of 16kbps is different from them. Is it in 16th channel as normally. Is there any other form of signaling other than CASE. I want them for my PHD thesis as i dont know how the E1 mapping is done in case of GSM traffic.
Hi Dino,
For a thesis, consider reading the 3GPP…
The TRX is indeed using 16kb/s channels on Abis to carry the voice. The signalling of all calls of a TRX is carried over the “RSL” (radio signalling link).
Basically, 1 TRX is connected to 2 ABIS timeslots for the voice (8 x 16kb/s) and 1 RSL. The RSL can be carried over 16kb/s or 32kb/s or 64kb/s, it depends on the signalling load, and the choice made by the OMCR configurator.
Cheers,
pixHow Abis work in order to interface between BTS and BSC?
osman,
it just transmits the info from one side to the other side, with as less errors as possible.
very simple job, indeeed…hI,
I WANT TO KNOW THE ACTUAL PHYSICAL LINK BETWEEN bsc AND MSC WHETHER ITSA OPTICAL OR RADIO LINKRajesh
it can be optical, it can be radiolink, it can be wireless loop, … or a direct E1 links twisted pairs (if very nearby)
or any combination of the above 🙂cheers
pixhow does E1 work in an Abis interface between BTS and BSC
