Tracking target in cluttered environment using multilateral time-delay measurements
Dragana Carević · The Journal of the Acoustical Society of America · 2004
The problem considered here is that of tracking a single underwater target in clutter using multilateral time-delay measurements derived from short-duration acoustic emissions, or transients, radiated by the target. The target is moving linearly with constant velocity and depth. To account for the effects on the time-delay estimates due to acoustic propagation in uncertain environments, the time-delay measurement errors between pairs of sensors are modeled using Gaussian mixture distributions. An approach is proposed that utilizes an iterative maximum likelihood optimization technique based on the expectation-maximization algorithm. In each iteration a nonlinear least-squares procedure is used to compute the target model parameters. A detection mechanism is also formulated that can validate the correctness of the estimated track parameters and verify the existence of a target. The proposed method is tested using simulated time-delay measurements from a linear array of three equally spaced sensors mounted onboard an observer platform. Extensive tests are performed for several scenarios with different tracking geometry.