The present document specifies the speech codec to be used for the GSM half rate channel. It also specifies the test methods to be used to verify that the codec implementation complies with the present document. The requirements are mandatory for the codec to be used either in GSM Mobile Stations (MS)s or Base Station Systems (BSS)s that utilize the half rate GSM speech traffic channel.

The following documents contain provisions which, through reference in this text, constitute provisions of the present document.

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