Test method of echo cancel function

A technology of echo cancellation and test method, which is applied in the direction of line transmission monitoring/testing, transmission monitoring, line transmission components, etc., which can solve the problems of in-depth testing in the testing stage, failure to provide test results, and inconvenient development costs, so as to improve development efficiency. , easy to analyze and solve problems, and save costs

Inactive Publication Date: 2004-09-15
BEIJING ELECTRIC POWER ECONOMIC RES INST +1
View PDF1 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

And according to this U.S. patent, it is necessary to develop actual equipment, which brings inconvenience and increases development cost
In addition, the U.S. patent can only give a conclusion on whether the echo canceller is qualified or not un

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
  • Test method of echo cancel function
  • Test method of echo cancel function
  • Test method of echo cancel function

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0058] In order to fully understand the testing method of the present invention, the working principle and mode of the echo canceller are firstly analyzed. like figure 1 The basic principle adopted for the echo canceller, the far-end speech x(n), the near-end speech v(n), simulates the signal x(n) reflected off the hybrid circuit as x(n) passing through an unknown echo channel, producing An echo signal y(n), which is added to the near-end voice signal to form r(n). The input of the adaptive filter is x(n), and the output is the echo replica signal echo residual signal To adjust the coefficients of the filter so that the echo replicates the signal The echo signal y(n) is tracked to cancel the echo signal. The echo canceller, which is the test object of the present invention, is basically realized by using this principle. The update of its filter coefficients follows the following principles:

[0059] w ( n + ...

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

A testing method of a echo balancing out function is to collect the signal producing in actual or making in order, to handle the signal according to each stage of hypothesis echo channel to create a corresponding echo, to use the orginal signal and eacho as the inputs of far end and near end, to catch output signal and filter cofficient and to restore is as curve as well as to compare it with the expected result. With the above steps, the right realization ability test of the echo balancing out code, the function perfect test, efficiency test, working condition test of the boundary point, health and strong test and comprehensive test could be carried out.

Description

technical field [0001] The invention relates to a test technology of a communication system, in particular to a test technology of an echo cancellation function in a communication system. Background technique [0002] At present, the user telephones are connected to the telephone office through a second-line line (called subscriber loop) that supports bidirectional transmission, but in the long-distance telephone transmission system, in order to facilitate voice transmission, the two transmission directions must be connected to two separate on the line, thus forming a four-wire circuit. A device that connects two-wire and four-wire parts is called a hybrid circuit. Due to the echo generated by the impedance mismatch of the hybrid circuit, the voice signal from the speaker cannot be completely transmitted to the receiver's phone, and the reflected voice signal is transmitted through the reverse line and returns to the speaker's phone, making the speaker listen To his own an...

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
IPC IPC(8): H04B3/23H04B3/46
Inventor 张震玮
Owner BEIJING ELECTRIC POWER ECONOMIC RES INST
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