Patent Document ID: 4333170
Application ID: 05853207
Patent Status: 1

Claim One:
1. An acoustical detection system for detecting targets which generate acoustical signals comprising: at least one pair of acoustical transducer means for receiving acoustical signals from said targets and transducing said acoustical signals to electrical signals having a plurality of frequency bins, said transducer means being spaced from each other, means for converting said electrical signals from analog signals to digital signals, means for processing said digital signals to generate phase difference signals in accordance with the phase differences between each of the frequency bins of the signals received by said pair of transducer means, means for dividing each of said phase difference signals by a signal in accordance with the frequency of the frequency bin associated therewith to generate phase difference slope signals for each of said frequency bins, means for grouping together signals representing common phase difference slopes, the signals in each such grouping representing signals emanating from a common target, and means for processing each of the groupings of signals to determine the direction and identity of each of the targets.