AMR: Discontinuous TX (DTX)

Mobile Battery life will be prolonged or a smaller battery could be used for a given operational duration. From the network point of view, the average required bit rate is reduced, leading to a lower interference level and, hence, increased capacity.

How to acheive DTX in AMR?
- Voice Activity Detector on TX side
- Evaluation of the background acoustic noise on the TX side
- Transmission of comfort noise information to the RX side using SID at regular intervals
- Generation of comfort noise on the RX side during periods when no normal speech frames are received.