Microphone Arrays 指導老師  尤信程 博士 研究生  許朝銘 時間  2001/11/29 13:30

Outline Introduction Mathematical Development Applications References

Introduction What ’ s a microphone array system? – A system capturing sound source information with more than one microphone. – The locations of microphones can be random or in some kind of order.

Introduction What capabilities a microphone array system has? 1. Source location : The different time delay of the received signals can be used to detect source position. 2. Source capture : The microphone arrays can providing enhanced SNR to conventional microphones. 3. Dereverberation :

Mathematical Development(1) Suppose we have a sound source S located at the Cartesian coordinates(x S,y S,z S ), a noise source NS located at (x NS,y NS,z NS ), and N microphones M 1, …,M N with the respective coordinates(x Mi,Y Mi,z Mi ) i=1 … N;

Mathematical Development(2) The signal emitted at the sound source is defined as S(t). The sound M j ’ (t) received at microphone j due to the sound source can be seen to be: Similarly, the noise source is defined as NS(t), and the M j ’’ (t) received at microphone j due to noise source can be seen to:

Mathematical Development(3)

Mathematical Development(4)

Applications

References [1] Daniel V. Rabinkin, ’ Digital Hardware And Control For A Beamforming Microphone Array, ’ Master Thesis,New Brunswick, The State University of New Jersey Jan