Bearings-Only Underwater Target Motion Analysis Based on Fifth-Degree Cubature Kalman Filter and RTS Smoother

target motion analysis problem known as target tracking addresses to estimate target state variables include position and speed. Underwater target tracking is significant importance due to underwater equipment have an ability to stay hidden. In this paper, bearings-only measurement Which is considered one of the most important tracking methods in military applications is used for tracking of the single underwater target. Purpose of this paper is to present novel structure for solving bearings-only tracking problem in the 2D coordinate. This method is based on a combination of fifth-degree cubature Kalman filter and Rauch-Tung-Striebel (RTS) smoother. Proposed structure includes two levels named forward filtering and backward smoothing. Monte Carlo analysis of the Simulation results shows that this structure can be used as an alternative solution for bearings-only underwater target tracking.