AMR is used for the 3G i’m trying to install on my asterisk. But i think this codec can’t be used on SIP, it should be the problem when i do a SayDigits with my softphone on SIP.
I think the codec AMR is simply used by the H324M (3G) gateway to make a call to a mobile phone.
If i’m right, I don’t really have a problem because I tried this codec on SIP…
AMR is used in 2G & 3G - its main interest is that it can use less bandwidth than the traditional GSM codec (AMR is variable bit rate), you tend to save 50% of bandwidth. This is a great tool for mobile operators who want to extend their network capacity without adding towers.