Underwater Signal Enhancement Using A Sine-wave Representation

Abstract

A new approach to interference suppres- sion is developed to enhance the audibility of under- water acoustic signals. The method, developed in a sine-wave analysis/synthesis framework, is integrated with time and frequency modiflcatiolns for further sig- nal enhancement. The signal to be processed can be measured from a single channel with. no constraints on the direction of arrival of the component signals. Inter- fering signals are modeled by single or multiple tones which are amplitude and frequency :modulated. Three sources of interference are being addressed: man-made signals (e.g. active sonar), biologics (e.g. porpoise), and geologics (e.g. ice). The enhancement techniques are robust in a large range of random noise environ- ments.