Direction estimation based on sound intensity vectors

The direction of a sound source in an enclosure can be estimated with a microphone array and some proper signal processing. Earlier, in applications and in research the use of time delay estimation methods, such as the cross correlation, has been popular. Recently, techniques for direction estimation that involve sound intensity vectors have been developed and used in applications, e.g. in teleconferencing. Unlike in time delay estimation, these methods have not been compared widely. In this article, five methods for direction estimation in the concept of sound intensity vectors are compared with real data from a concert hall. The results of the comparison indicate that the methods that are based on convolutive mixture models perform slightly better than some of the simple averaging methods. The convolutive mixture model based methods are also more robust against additive noise.