APPARATUS SUPPRESSING ACOUSTIC ECHO SIGNALS FROM A NEAR-END INPUT SIGNAL BY ESTIMATED-ECHO SIGNALS AND A METHOD THEREFOR

摘要

In an echo suppressing apparatus suppressing from a near-end input signal acoustic echo signals caused by a far-end signal, an estimated-echo path characteristic is multiplied by a far-end signal to produce an estimated-echo signal for each frame, and frames of the estimated-echo signals thus obtained are stored in an estimated-echo signal storage. A delay amount estimator calculates the total of differences between the near-end input signal and each estimated-echo signal thus stored, and determines the amount of frame delay having its total of differences minimal. A delay estimated-echo signal calculator uses the amount of frame delay to read out an optimum frame and near frames respectively preceding and following the optimum frame and to calculate a corrected, delay estimated-echo signal. An echo suppressor uses the estimated-echo signal thus corrected to suppress the acoustic echo signals from the near-end input signal.

主权项

1. An echo-suppressing apparatus suppressing from a near-end input signal an acoustic echo signal caused by part of a far-end signal, said apparatus comprising:
an estimated-echo signal storage storing therein a plurality of frames of estimated-echo signals, each of which is obtained by multiplying an echo path characteristic estimated one frame earlier by the far-end signal for each frame on a time sequence; a frame delay amount estimator calculating a total of differences between the near-end input signal and each of the estimated-echo signals stored in said estimated-echo signal storage, and determining an amount of frame delay having the total of differences minimal; a delay estimated-echo signal calculator using the amount of frame delay to read out an optimum frame and a near frame preceding or following the optimum frame for calculating out a corrected, estimated-echo signal; and an echo suppressor using the corrected, estimated-echo signal for suppressing the acoustic echo signal from the near-end input signal.