Acoustic source localization

From Wikipedia, the free encyclopedia

This article (or section) may need to be wikified to meet Wikipedia's quality standards.
Please help improve this article, especially its section layout, and relevant internal links. (help)
This article has been tagged since January 2007.

Acoustic source localization is the task of locating a sound source given measurements of the sound field at several disparate locations. Microphone arrays are typically employed for the sampling of the spatial sound field. Some have termed acoustic source localization an "inverse problem" in that the measured sound field is translated to the position of the sound source.

Central to the acoustic source localization problem is the cross-correlation function between two microphones, defined as:

$R_{x_1,x_2} \left( \tau \right) = E \left\{ x_1 \left( n \right) x_2 \left( n + \tau \right) \right\}$

which defines the level of correlation between the outputs of two microphone $x 1$ and $x 2$ . In general, a higher level of correlation means that the argument $τ$ is relatively close to the actual time-difference-of-arrival (TDOA) between the two microphones for the source:

$\tau_{\mathrm{true}} = \frac{d_{s,1}-d_{s,2}}{c}$