[Charlie]

Hi

I am very new to GSM network and already I am ecountering basic problems.

sampling frquency for voice is standardised to 8Khz…which means (i guess) that a voice signal is sampled every 0.125ms (right?)..but a GSM channel (Time slot) last for 0.577ms…which is too long for the next sample…how was this value (0.577ms) worked out ?
regards
Charlie

[serena]

hi charlie

pls note that the time slot isnt the one thats doing the sampling. In one time slot there could be a number of samples that are taken through.

[Arun]

How can i improve the Quality of GSm Networks.Pls give me the basics and guidelines related to this topic.

[Muzammil]

Hi Charlie,
Sampling freq. for Voice is 8Khz for PSTN, i.e, there are 8000 voice samples/sec. And We ger .125ms is 1/8000. You are right!. This is very true to the PSTN trunks.
But in GSM traffic channels, due to the scarcity of open air frequencies. The vocie channel in GSM network (in Air Interface) is 13kbps. And the framing methods are also entirely different from the PSTN trunks.

Below link is the detailed overview of GSM technology …
http://ccnga.uwaterloo.ca/~jscouria/GSM/gsmreport.html

In the report u can find the framing information and the air interface specs.

[Stefano]

Hi Arun,
could you explain better your topic ?

[faris]

hi all
can nyone tell me how they rech the standard in GSM :8 time slot per frame

[Arun]

What are the basic thing which i need to take care in the planning of BSC Planning in a Network.Also please tell me the basic things for BSC Integaration which ralates to their planning in the new network.

Also if possible,give me the details about frequency hopping.

[Sanjeev]

Hi All,

Can any1 explain me what are the advantages of SS7 over R2MF signalling ?

Regards
Sanjeev

[Monica]

Hi Sanjeev,
SS7 is CCS signaling whereas R2MF is CAS signalling.

Suppose if u have ten PCM stream connectivity between ur exchange and other exchange , then in case of SS7 signalling only one signalling channel (64Kbps of any PCM stream) is sufficient so totally u will get (10*31-1{sig})= 309 traffic channels (64 Kbps of each), implied it can carry 309 simultaneous calls with one (64kbps) signalling channel.

In case of R2MF signalling its mandatory that u have to reserve one channel (64Kbps) per PCM stream so if have ten PCM streams between exchange u will get
(30*10) 300 traffic channel.

Visit Cisco web site to get fundamentals

I hope i made it clear

[Arun Verma]

I m having 2 BSC’s of Ericsson in my network.Now we are thinking to switch over to Nokia BSC’s.So we are planning to make 5 BSC’s of Nokia in comparison to 2 BSC’s of Ericsson.So what are the basic parameters and things which i need to take care about these BSC’s.i mean to say that what kind of Precautions i need to take care before making my city into 5 BSC’s of Nokia

[Sanjeev,]

Tahnx Monica,

Let me know are ther any more advantages of ss7 , from one of the document I got that CIC or traffic channel will not be engaged until the distant party picks up the receiver, is it true.

[Tech]

Hi Arun Varma,

Are you working in India ?
I would like ask some more question regarding AXE-BSC.

Can you send me a mail to telecomtech@rediffmail.com

Rgds

[Hans]

Arun Verma,

Can I have your email so I can send you some questions re the ERI BSC’s

[Arun verma]

My mail id is arun23mail@yahoo.com
So, i think we can talk now.

[prakash raj bhatt.]

hi ALL
ANY ONE HELP ME FOR THE KNOWLEDGE ABOUT
SATELLITE SYSTEM.

[Author]

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