Hello Nordin, On Wed, 29 Jul 2009 11:51:59 +0200, "Nordin" <bouchtaoui@gmail.com> wrote:

I can't find a good link about how several MSs on one ARFCN can send and receive speech data.

Have a look at the following, the first is a general introduction with good references to the GSM specification, the second is about speech coding: http://en.wikipedia.org/wiki/Um_Interface http://www.gsmfordummies.com/encoding/encoding.shtml Best regards, Dieter -- Dieter Spaar, Germany spaar@mirider.augusta.de