A Group Member Adaptive Echo Cancellation Method Based on Correlation Entropy Induction

Abstract

A kind of self-adaptive echo cancellation method based on the set member of correlation entropy, its steps are as follows: A, far-end signal acquisition, the far-end signal that far-end transmits is sampled, can obtain the discreteness of the far-end input signal of current moment n Value x(n), whose 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 the current moment n through the adaptive filter, and its output value y (n) is the estimated value of the echo signal; C, echo cancellation, obtain with near-end microphone sampling Subtract the estimated value y(n) of the echo signal from the near-end signal d(n) at the current moment n with echo; D, update the filter tap weight coefficient, and calculate the tap weight vector of the filter at the next moment n+1 w(n+1), w(n+1)=w(n)+μ(n)U(n)(U T (n)U(n)) ‑1 E(n)-C(n); E. Let n=n+1, repeat the above-mentioned process of A, B, C, D, E until the call ends. This method can obtain faster convergence speed and low steady-state error, and the effect of echo cancellation is good.

Description

technical field [0001] The invention belongs to the technical field of echo cancellation in communication systems. [0002] technical background [0003] As a branch of information processing, adaptive signal processing technology has developed rapidly in recent years and has been widely used in the field of communication. The echo phenomenon in communication systems refers to the sound or signal being reflected back to the signal source after delay or deformation. Since the echo phenomenon will seriously affect people's call quality, how to eliminate the echo has become a focus of attention. The communication echo can be adaptively eliminated through the system identification model: the identified system is an echo channel, and the output of the system identification is the estimate of the echo signal, and the echo can be eliminated by subtracting the voice signal containing the echo signal from the estimate of the echo signal . Adaptive echo cancellation technology has t...

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Problems solved by technology

However, when the system is a sparse echo channel, most of the tap weight vector w(n) of the system at the current moment n is close to zero or zero, and is disturbed by background noise, so that the tap weight vector update value w(n+1 ) changes too much, resulting in a large steady-state error, and the effect of echo cancellation needs to be improved

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