Cooperative multiple-target tracking using wavelets

Noisy environmental conditions significantly reduce the ability to track multiple-targets in sonar imaging systems. The dynamics of the target as a function of time is viewed as a 2-D image in which tracks are viewed as edges. Wavelet analysis is used in the first part of this paper to perform the edge detection, or multiple target tracking, by finding the modulus maximas of the dyadic wavelet transform of the sonar image at different scales. The second part of the paper addresses the complex problem of decentralized multiple target tracking with local decisions. Using the approach developed in the first part of the paper, the high resolution information is wavelet decomposed into multiresolution form with the lowest resolution matching that of the other sensor. An edge mask is created, compressed and transmitted to the low resolution sensor which uses this mask as a weighing function on its wavelet transform. We show that this technique is highly effective in highlighting the targets' tracks information in the low resolution noisy sensor.