Passive Location Method Study Based On Azimuth Angle And Azimuth Angle Changing Rate

To deal with the wide application of electronic-counter, electronic jamming and anti-radiation missile, it is required to enhance the viability and antijamming ability of each electronic reconnaissance equipment. As an important part of the traditional electronic reconnaissance equipments, active locating system has not met the requirements of modern war because of its own drawbacks. Hence, sin- gle station passive locating system has gradually received extensive attention for the advantages of being hard to be detected, strong antijamming ability and long detecting range. Based on Azimuth Angle and Azimuth Angle Changing Rate system, the system's observability and filtering divergence are researched in this thesis. The main works can be summarized as follows.Firstly, several technology problems of passive localization and tracking are discussed. Specially, some advanced localization theory with higher precision and fast speed is introduced. It significantly improves the performance of localization and tracking system. In last years, the extended kalman filter EKF algorithm has become the usual algorithm to deal with the nonlinear dynamic systems. Unfortunately, because of the linearization, the EKF produces large errors and easily lead to divergence. To overcome this problem, the unscented kalman filter EKF algorithm is introduced in the dissertation. This algorithm estimates the posteriors with some typical sigma point. It amends flaws of the EKF, and has better properties such as robustness and accuracy. In the two conditions that the receiver can or can't receive: the LOS, the EKF and UKF algorithms are both studied, the tracking performance is compared by the computer simulation. The method is proven to be effective.Secondly, In the light that the single observer passive location system has no source fixed position,only the arrive cape as the prognosis quantity can't locate the static target and would take long time for locating dynamic target and result in bad accuracy and real-time performance. With observation post in even acceleration move, a location method is proposed, which takes angle changing rate as observation value. Simulation shows that, with observation post in even acceleration move and by making use of arrive cape and angle changing rate, the location tracing of high-speed object can be carried out, and a prognosis quantity with highly accurate location and fast convergence is thus obtained, which is the proposed algorithm can still accurately track the target while useing UKF.