AMR

[Tameem]

can any one please tell me what is AMR how may codec can we use .do these codec change automatically when the sqi is bad

[RF engineer]

can any one please tell me what is AMR how may codec can we use .do these codec change automatically when the sqi is bad
AMR is type of speech code like FR,HR and EFR. it can be used 4 AMR full rate codes and 3 AMR half rate and the change from code to code depend on C/I.
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