Microphone possessing function for cancelling out echo

Abstract

The microphone includes mini head amplifying circuit A, echo canceling circuit, amplifying circuit B and attenuation circuit. Mini head collects sound, and converts sound signal to electric signal. Circuit A magnifies signal collected by mini head, and outputting the magnified signal to the echo canceling circuit. One route split out from the output of videoconference terminal as a reference sound signal is inputted to the attenuation circuit. Being attenuated to proper level, the inputted signal is as referenced signal of echo canceling process. The echo canceling circuit carries out canceling process for mini head signal and the reference sound signal from the attenuation circuit in order to cancel component of reference sound signal from the mini head signal. The signal of processed result is output to circuit B, which amplifies the signal, and the amplified signal is input to videoconference terminals. The invention restrains echo interference and raises quality of sound.

Description

technical field [0001] The invention relates to a microphone, in particular to a microphone with an echo cancellation function. Background technique [0002] Acoustic echo cancellation is an indispensable function in the video conferencing system. During the meeting, the sound of the remote site will be reproduced by the speakers of the local site. Through the space propagation path, the microphone of the local site will collect this sound. If there is no acoustic echo cancellation processing at this time, the sound It will be transmitted back to the remote site, and the remote site will hear its own voice, which will form echo interference. figure 1 It is a schematic diagram of the sound transmission path of the video conferencing system. Such as figure 1 As shown, in the case where there are two meeting places A and B holding a video conference, a sound b is emitted from the meeting place B, which is collected by the microphone B and sent to the video conference termina...

AI Technical Summary

Problems solved by technology

[0003] Microphones currently used, including those used in video conferencing systems, generally do not have the function of acoustic echo cancellation, and cannot perform acoustic echo cancellation

In the video conferencing system, if the conference terminal does not do acoustic echo cancellation processing, it will inevitably bring about the problem of echo interference

On the other hand, even if the acoustic echo cancellation process is added to the videoconferencing terminal, this method of collecting sound by the microphone and sending it to the terminal, and the echo cancellation process by the terminal also has disadvantages: due to different types of microphones, the collected sound The frequency spectrum and the volume of the output are different, and some of them are quite different, and the effect of echo cancellation processing is greatly affected by the frequency spectrum and volume of the sound.

This limits the use of the specified type of microphone for the video conferencing terminal, and the misuse of other types of microphones will have a negative impact on the echo cancellation effect of the terminal

In addition, the current method of implementing echo cancellation on video conferencing terminals generally uses software calculations, which is relatively difficult to implement. In addition, processors are used for calculations, which is costly and increases the complexity of the terminal.

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