A new tracking filter is proposed for the highly non-linear single observer passive location and tracking (SOPLAT) system based on the observation of bearing, bearing rate and difference time of arrival of emitter. The new method used the Jerk model for the maneuvering target, and then used the IMM algorithm basing UKF to keep the tracking of the emitter. By using this method, the precision of the tracking filter can be improved, and it is also good to the filter's stability. The simulations proved the feasibility and availability of the new method. At last, further research directions of the IMM-Jerk were discussed.