Selective time-reversal block solution to the stereophonic acoustic echo cancellation problem

Stereophonic acoustic echo cancellation (SAEC) plays an important role in delivering realistic teleconferencing experience. However, the problem of stereophonic acoustic echo cancellation is challenging due to the requirement of uniquely identifying two acoustic paths. In this paper, we present a novel method of selective time-reversal block transformation that significantly reduces the misalignment without noticeably affecting the audio quality. The proposed method employs a magnitude detector so that input blocks of one channel with average magnitude less than a specified threshold are time-reversed in order to decorrelate the other channel. Simulation results show that the proposed method achieves higher convergence rate, better spatial information with less audio distortion compared to the well-known half-wave rectifier method.