Proportional affine projection echo elimination method based on coefficient difference

Abstract

The invention provides a proportional affine projection echo elimination method based on coefficient difference. The method includes the steps of (A) far-end signal sampling, (B) echo signal estimation, (C) echo signal removing, (D) updating of filter tap weight coefficients, and (E) repeating of the steps B, C and D on the condition that n is equal to n plus one, and real-time echo elimination can be achieved. When the tap weight coefficients are updated in the step D, the step length gi (n) of the ith tap weight coefficient wi (n) of a self-adapting filter at the current moment satisfies an equation shown in the text, namely, in the time period M, the step length of the tap weight coefficient of the self-adapting filter at the current moment is equal to the difference value of any tap weight coefficient at the current moment n and the tap weight coefficient at the initial moment kM of the time period, and when the weight coefficients are updated, the affine projection method of an input signal matrix formed by input signal vectors at multiple moments is adopted. According to the method, the echo elimination effect is good, environment self-adaptability is high, the convergence rate is high, steady state errors are small, meanwhile, computation complexity is low, cost of needed hardware is low, the structure is simple and the method is easy to carry out.

Description

technical field [0001] The invention belongs to the technical field of echo cancellation in communication. Background technique [0002] The advancement of information technology is affecting all aspects of people's lives and has brought profound changes to human social life. As an important aspect of information technology, communication technology has been greatly developed, and echo cancellation in the communication process is a hot spot that has attracted much attention and challenges in this field. The sound will form an echo after multiple reflections in a closed space, and the echo will also be formed in the signal transmission due to the impedance mismatch in the transmission medium. 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 containin...

AI Technical Summary

Problems solved by technology

However, the IPAPA algorithm is still a compromise between the PAPA algorithm and the APA algorithm in essence, and its convergence speed cannot be further improved.

Moreover, the performance of the IPAPA algorithm is highly dependent on the adjustment parameters, and the adjustment parameters depend on the structure of the target impulse response, and cannot be adaptively adjusted

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