Integrating Acoustic Echo Cancellation In LPC-based Speech Coders

This paper presents a novel acoustic echo canceller (AEC) consisting of an adaptive FIR filter and a double-talk detector. By employing the widely used LPC-based speech coder for decorrelation, we develop a variable step-size decorrelation NLMS algorithm for the adaptive FIR filter and an echo-path mismatch detection algorithm for the double-talk detector. This new approach reduces the computational complexity from 0(N²) to O(N) for both algorithms of echo cancellation and double-talk detection. Simulation results show that the proposed algorithms improve the performance of both echo cancellation and double-talk detection greatly compared to other algorithms