Bearings-only tracking using derived heading

In conventional bearings-only tracking, the target states are estimated from just the bearing measurements. The accuracy of these estimates can be improved by using the heading, which can be derived from a set of measured bearings, as an additional measurement. In this paper, the target heading has been computed from a set of bearing measurements. This, along with bearings, has been used to obtain state estimates. The Cramer-Rao lower bounds for these estimates is derived and compared with that of the conventional bearings-only tracking. The use of derived headings improves the position estimates during target maneuver. This technique has been applied to multi-target tracking and is found effective particularly during target crossing. The tracking results are obtained using particle filters and compared to that of an extended Kalman filter implementation. The simulation results demonstrate the improved estimates obtained for certain target states.