Adaptive Range Tracking of Underwater Maneuvering Targets Using Passive Measurements

Abstract

This paper examines the problem of adaptively tracking in range and velocity a maneuvering target using passive time delay measurements. The target is free to maneuver in velocity and to make depth changes at times unknown to the observer.

Tracking is accomplished by using the basic polar model of target and observer motion previously developed and reported upon [1],[2]. Now however, a nonlinear prefilter has been added to the tracking system. This leads to two major benefits: the first, is that the need for extended Kalman filters is completely eliminated which gives the passive tracking system a much greater degree of “robustness” than it previously had. The second benefit is a decoupling of depth estimation from the polar range estimator, which considerably reduces the computational level of the adaptive tracking system.