Analysis of two structures for combined acoustic echo cancellation and noise reduction

This paper addresses the problem of speech enhancement in the context of GSM hands-free radiotelephony where the signal to be transmitted is corrupted by background noise and echo signals. We analyze possible schemes for combined acoustic echo cancellation (AEC) and noise reduction (NR) devices. Considering two AEC algorithms and one NR device, we show that the overall performances obtained by these schemes are greatly dependent on the intrinsic behaviour of the considered AEC algorithms. These results are confirmed by informal listening tests presented in that contribution.