Tracking and length estimation of underwater acoustic target

Underwater acoustic multi-target tracking using bearing, Doppler and a conventional filtering method to determine the target location has problems such as low precision and inaccurate identification. Target echo time broadening is used first for the tracking process. The length of the target can be derived from the echo broadening, and the target length is obtained as a parameter by expectation-maximisation derivation, thereby increasing the dimension of the measurement for the estimation. Simulation results show that this method has higher tracking accuracy and target recognition accuracy than do other feature-aided tracking methods.