Patent Document ID: 4847817
Application ID: 07140189
Patent Status: 1

Claim One:
1. A method of utilizing a broadband sonar having a Q of between 2.5 and 3.5 for target discrimination in accordance with time separation and amplitude of echo highlight features that the human auditory system uses comprising: ensonifying known targets in the water with multiple broadband transient signals; receiving echoes from each of the known targets; extracting time-domain feature data from the known target echoes to construct a library of target features based on the time-domain feature data of position and amplitude of echo highlights at which the slope of an envelope detected signal changes from positive to negative; ensonifying at least one unknown target by substantially the same multiple broadband transient signals; receiving echoes from the unknown target; extracting time-domain feature data from the unknown target echoes in the same manner as for the known targets which consist of time-domain feature data identifying the position and amplitude of unknown target echo highlights in which the slope of the envelope of the detected signals changes from positive to negative; comparing the time-domain feature data of echoes from the unknown target with time-domain feature data of the known targets to enable a recognizing and discrimination of targets of interest; and storing the time-domain feature data from the known target echoes prior to the step of comparing, the steps of extracting include obtaining the Hilbert transform from a fast Fourier Transform of the envelope of the echoes to arrive at an analytic signal for a feature extraction of the time-domain feature data.