Cloaking method based on difference beam forming

Abstract

The invention discloses a cloaking method based on difference beam forming. According to the method, by means of short time Fourier transform, a time-domain signal received by a sensor array is decomposed into frequency-domain sub-band signals, cloaking filters based on N-order difference beam forming are constructed on various sub-bands, therefore, a sound signal from a sound source within the cloaking distance passes through the cloaking filters in an unattenuated mode, and finally an estimated signal is obtained through inverted STFT. The cloaking method has the good cloaking effect.

Description

technical field [0001] The present invention relates to a sound hiding technology based on a microphone array, in particular to a sound hiding method based on differential beam forming. Background technique [0002] The research on hidden sound technology has a long history. People have mainly explored two methods in the field of acoustic signal sensing: bone conduction microphone and ultrasonic microphone, and explored signal separation technology and differential microphone array in the field of acoustic signal processing. [0003] Bone conduction microphones use the slight vibration of the head and neck bones caused by human speech to collect sound signals and convert them into electrical signals. Because it is different from traditional microphones that pick up sound through air conduction, it can also transmit high-definition sound in a very noisy environment. As early as hundreds of years ago, people had many practical applications of bone conduction technology, but t...

AI Technical Summary

Problems solved by technology

Although bone conduction microphone technology has made a breakthrough, the current promotion of its communication earphones is not very ideal. There are several problems: 1) poor dynamic effect; 2) high cost; 3) poor packaging effect; 4) poor sound quality

However, the separation performance achieved by the current separation technology is still very limited, which cannot meet the needs of hidden sound applications.

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