Defense applications of Edmund J. Sullivan’s acoustic signal processing concepts and methods

Abstract

Passive acoustic signal processing for defense involves the detection, classification, localization and tracking of sound sources. Ed Sullivan posited that “acoustic signals carry information in their kinematics, as well as their spatial and temporal phase structure, so that including information in the signal model will provide enhanced performance.” This idea is applied to the practical defense problem of locating the point-of-origin of hostile sniper fire by processing the acoustic signals sensed by a receiving array. Superior acoustic source localization performance is achieved by including the deceleration of the bullet in the signal model. Next, Ed’s passive synthetic aperture methods are applied to the inverse problem of estimating the source (or rest) frequencies and flight motion parameters of turboprop aircraft and helicopters using a single acoustic sensor and then, an array of sensors. In this case, the source signal is temporally coherent and the source kinematics is contained in the received Doppler-shifted signals. Finally, source localization of broadband signals using cross-correlation methods is observed to fail when the different phase structures of the received signals lead to them being uncorrelated, which can be remedied by differential Doppler compensation.Passive acoustic signal processing for defense involves the detection, classification, localization and tracking of sound sources. Ed Sullivan posited that “acoustic signals carry information in their kinematics, as well as their spatial and temporal phase structure, so that including information in the signal model will provide enhanced performance.” This idea is applied to the practical defense problem of locating the point-of-origin of hostile sniper fire by processing the acoustic signals sensed by a receiving array. Superior acoustic source localization performance is achieved by including the deceleration of the bullet in the signal model. Next, Ed’s passive synthetic aperture methods are applied to the inverse problem of estimating the source (or rest) frequencies and flight motion parameters of turboprop aircraft and helicopters using a single acoustic sensor and then, an array of sensors. In this case, the source signal is temporally coherent and the source kinematics is contained in the received...