Acoustic Echo Cancellation Embedded in Smart Transcoding Algorithm between 3GPP AMR-NB Modes

Table 1

Overall Echo Return Loss Enhancement.

(a) Transcoding from AMR-NB 12.2 kbps mode to 7.4 kbps mode

SER	11 dB (ℎ1)	15 dB (ℎ1)	17 dB (ℎ1)
Standard NLMS (ERLE)	11.7 dB	9.1 dB	9 dB
Proposal AEC (ERLE)	49.3 dB	40.3 dB	40.7 dB

(b) Transcoding from AMR-NB 7.4 kbps mode to 12.2 kbps mode

SER	11 dB (ℎ1)	15 dB (ℎ1)	17 dB (ℎ1)
Standard NLMS (ERLE)	8.3 dB	4.6 dB	5.4 dB
Proposal AEC (ERLE)	55.7 dB	39.1 dB	49.7 dB