An Adaptive Echo Cancellation Method Against Shock Interference

Abstract

A kind of anti-impact noise interference M estimate decorrelation proportional adaptive echo cancellation method, its steps are as follows: A, far-end signal collection, sampling the far-end signal that far-end transmits, can obtain the far-end of current moment n The discrete value x(n) of the input signal, its filter input signal vector is x(n)=[x(n),x(n‑1),...,x(n‑L+1)] T ; B, echo signal estimation, pass the input signal vector x (n) of time n through the adaptive filter, and its output value y (n) is the estimated value of the echo signal; C, the decorrelation operation of the input signal, calculate the correlation coefficient a(n), obtain the update vector z(n) of the adaptive filter tap weight vector w(n); D, echo cancellation, use the near-end microphone sampling to obtain the near-end signal d(n) of the current moment n with echo ) minus the estimated value y(n) of the echo signal; E, filter tap weight coefficient update, calculate the evaluation function ψ(e(n)) updated by the tap weight vector w(n) of the filter at the current moment n and update Step size matrix G(n); F, let n=n+1, repeat the above-mentioned process of A, B, C, D, E until the end of the call.

Description

technical field [0001] The invention belongs to the technical field of echo cancellation in communication systems. [0002] technical background [0003] Adaptive signal processing technology has a wide range of applications in the field of communication. The signals in the communication system are mainly voice signals, however, when a call is in progress, the echo will seriously affect the quality of the voice call. The echo phenomenon refers to the sound or signal being reflected back to the signal source after delay or deformation. This phenomenon widely exists in communication systems such as voice communication, data communication, satellite communication, hands-free phone, and teleconferencing system. For example, when making a phone call, because the speaker and the microphone are placed in the same space, the local near-end microphone will receive the far-end voice from the local speaker and send it back to the far end, which will cause the far-end speaker to hear h...

AI Technical Summary

Problems solved by technology

Among the product influence factors considered when the tap weight vector is updated in this algorithm, the influence factor related to the residual is directly the residual signal at the current moment. When there is impact interference, the "residual signal" is huge, resulting in the wrong tap weight vector. Huge update, reduced convergence speed, increased steady-state error, and still can't achieve good results when it resists impact interference

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