Sound stealth method based on differential beam forming

Abstract

The invention discloses a sound stealth method based on differential beam forming. First, a time-domain signal received by a sensor array is decomposed into frequency-domain sub-band signals through short-time Fourier transformation (STFT). Then, a sound stealth filter based on Nth-order differential beam forming is constructed on each sub-band so that sound signals of sound sources within a sound stealth distance can pass the sound stealth filters without attenuation. Finally, an estimation signal is obtained through inverse STFT. The sound stealth method has a good sound stealth 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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