Analytic type spatial de-aliasing method for microphone array

Abstract

The present invention relates to an analytical type spatial de-aliasing method for a microphone array. The method includes the following steps that: the microphone array receives sound source signals,and the sound source signals are converted into digital sound signals; the spectra of the digital sound signals are extracted, so that the spectra of the digital sound signals of each microphone in the microphone array can be obtained; a spatial correlation matrix at each frequency point can be estimated according to the spectra of the digital sound signals of each microphone; the spatial correlation matrix at each frequency point is decomposed, so that a main feature vector can be obtained, each component of the main feature vector is corresponding to the acquired signals of one microphone;time phase difference between any two microphones is obtained according to the main feature vector at each frequency point; and a periodic number combination is obtained through an anti-aliasing formula according to the time phase difference between the microphones, and an optimal periodic value can be found out from the periodic number combination.

Description

technical field [0001] The invention relates to the field of sound source localization and speech enhancement, in particular to an analytical spatial de-aliasing method for a microphone array. Background technique [0002] The method based on the microphone array occupies an important position in the speech signal processing. It can be used in remote conferences to locate the position of the speech recognition, indicate the direction of the beam focus for the microphone array, and provide pointing information for the conference camera. At the same time, it can separate and enhance the target source signal. [0003] In array processing, it is often necessary to calculate the time delay between a sound source arriving at two microphones based on the phase spectrum of the signal. However, phase is a periodic variable, and the real time delay is the sum of several time periods and phase time differences. When the distance between the microphones is large enough, there are sever...

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Problems solved by technology

[0004] In the existing literature, it is often possible to limit the distance between the microphones so that there is only one possible value for the number of cycles. However, the small size of the microphone array limits the performance of the array.

Another method is to check the rationality of each period value. However, for an array composed of several pairs of microphones, the combination of period values ​​may be a huge number, which can easily lead to a huge amount of calculation.

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