How compression is performed over GSM?

[testing test]

Hi,

I want to know how compression for voice is achieved in GSM networks? Is it performed in time-domain or frequency-domain and if someone has documentation related to GSM compression? I am looking for that.

Please help me in this regards.

Thank you.

 

[FvM]

A description of GSM voice codecs can be found at various places at the internet, e.g. GSM - Wikipedia, the free encyclopedia

ANSI-C code that represents the algorithms of the half- and full-rate codec can be downloaded at etsi.com