Patent ID: 7423587

Claim:
A method for performing a multiresolution decomposition of an input signal to a wave-based sensing array into a plurality of outputs of spatial bandpass filters comprising the steps of: a) generating at least two different types of directivity pattern for each of a plurality of frequency components in the input signal for each array sensor: at least one of the types being a center-type directivity pattern which concentrates the spatial sensitivity in a central main-lobe and at least one of the types being a surround-type directivity pattern which surrounds the direction of the center-type directivity's main-lobe with its most sensitive region; b) scaling the center-type and surround-type directivity patterns with frequency so that a plurality of different beam-widths are produced; c) forming center-type and surround-type bandpass channels by isolating frequency components corresponding to the center-type and surround-type directivity patterns via bandpass-filtering performed on the input signal of a single sensor, pairwise combining the outputs the center-type channels with the surround-type channels matching in spatial scale, and determining an amplitude difference between the channels.