Method for eliminating echo in echo eliminator and its dual end communication detection system

Abstract

The invention relates to an echo canceller, an echo cancellation method and the double-end talking detection system thereof, wherein, the echo canceller decodes a data stream from the network end into a far-end voice signal and extracts a short-time excitation signal as well as a linear prediction coding coefficient by utilizing a linear prediction decoder. Based on the linear prediction coding coefficient, the echo canceller carries out a decorrelation process to a residual signal by a decorrelation filter, and executes a normalized cross correlation process to the short-time excitation signal and the decorrelation residual signal by utilizing the double-end talking detector to generate the normalized cross correlation detection variable, hence, the echo canceller detects the existence of the double-end talking and then further controls the renewal of the self-adaptive filter. The invention is capable of detecting the existence of the double-end talking by the decorrelation process as well as the normalized cross correlation process to the far-end voice signal and the residual signal, thus obviously decreasing the calculation complexity of the double-end talking detection and the storage space consumption.

Description

【Technical field】 [0001] The invention relates to an echo cancellation system, an echo cancellation method and a double-talk detection system in a communication network, in particular to a double-talk detector (Doubletalk Detector, DTD) and a linear predictive coding (LPC) vocoder Combined echo canceller, echo cancellation method and double talk detection system thereof. 【Background technique】 [0002] In recent years, since the development of the Internet has promoted the wide application of VoIP (Voice over Internet Protocol) technologies such as VoIP and video conferencing, echo cancellation has become an indispensable and important module in voice communication. As shown in Figure 1, the most effective way to solve this problem is to use an adaptive filter to construct an acoustic echo canceller, and to simulate the echo path through the adjustment of the adaptive filter, so that its impulse response is close to the actual echo path , so as to obtain the echo prediction...

AI Technical Summary

Problems solved by technology

[0007] In order to solve the technical problems of high computational complexity and large storage space consumption of DT detection in the prior art, the present invention provides a DT detector combined with an LPC vocoder, thereby reducing the computational complexity and storage space of the detection method Consumption, improve the accuracy and reliability of detection

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