Method for eliminating combined step length proportional affine projection echo

Abstract

A method for eliminating combined step length proportional affine projection echo comprises the following steps of A, acquiring a sound signal x(n) transmitted from a far end at a telephone loudspeaker and acquiring an expected signal d(n) at a telephone microphone; B, using the sound signal x(n) as an input of an adaptive filter, and using the output of the adaptive filter as an estimated value d<^>(n) of an echo signal; C, performing echo offset, namely using an error signal e(n) obtained through subtracting d<^>(n) from d(n) as a clean signal after echo offset and transmitting the error signal to the remote end; D, calculating an error vector of the adaptive filter; E, calculating a weight updating increment deltaw(n) of the adaptive filter; F, calculating a combined step length mu(n); G, updating the weight vector w(n+1)=w(n)+mu(n)deltaw(n) of the adaptive filter; and H, setting n=n+1, repeating the steps A, B, C, D, E, F, G until the calling is finished. The method has advantages of high convergence speed and low steady-state error.

Description

technical field [0001] The invention belongs to the technical field of adaptive echo cancellation for telephone communication. Background technique [0002] In the telephone communication business, wherever the microphone and the loudspeaker are used at the same time, the acoustic echo will inevitably appear, which is the most important factor affecting the quality of the call. During a call, the voice of the speaker on the other side is played through the speaker of the phone, and is picked up by the microphone (microphone) of the phone directly (without any reflection) or indirectly (after one or more reflections from the house or objects in the house), It is transmitted back to the distant speaker so that he can hear what he said earlier, that is, the acoustic echo. The path of sound from the speaker to the microphone is called an echo channel, and its impulse response can be represented by a column vector. [0003] Acoustic echo affects call quality, for which research...

AI Technical Summary

Problems solved by technology

However, the MIPAPA algorithm also suffers from a trade-off between fast convergence and low steady-state error, which is attributed to the choice of fixed step size

To be precise, a large step size makes the algorithm converge faster, but the steady-state error of the algorithm is large; conversely, a small step size causes the algorithm to have a small steady-state error, but slows down the convergence speed

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