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

A technology of echo cancellation and coefficient, which is applied in the transmission system, echo reduction, wired transmission system, etc., can solve the problems of large storage space consumption and high computational complexity of DT detection, and achieve the effect of reducing computational complexity

Inactive Publication Date: 2008-01-16
PEKING UNIV SHENZHEN GRADUATE SCHOOL
View PDF0 Cites 39 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

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

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for eliminating echo in echo eliminator and its dual end communication detection system
  • Method for eliminating echo in echo eliminator and its dual end communication detection system
  • Method for eliminating echo in echo eliminator and its dual end communication detection system

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0026] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0027] The present invention is based on the principle of normalized cross-correlation, and in order to reduce its computational complexity, the function of de-correlation processing is added by combining with a vocoder.

[0028] As shown in Figure 1, in a traditional acoustic echo canceller, the far-end speech x(n) generates an actual echo y(n) through the echo path H, which is comparable to the near-end speech v(n) and the ambient noise n(n) After being superimposed, it becomes the microphone input signal d(n). The adaptive filter continuously adjusts the adaptive filter coefficients w(n), resulting in an estimated echo signal path will estimate the echo signal Subtracted from the near-end signal d(n), the residual signal e(n) is obtained. e(n) is sent to the remote end and used to update the coefficients of the adaptive filter.

[0029] Assume ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

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...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H04B7/015H04B3/23
Inventor 胡海军林茫茫李挥张军生张志军陈慕羿何伟王智韬张政操马建设
Owner PEKING UNIV SHENZHEN GRADUATE SCHOOL
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap