Study On Radar Tracking And Discrimination For Ballistic Missiles

The ballistic missiles are great powerful attacking weapons in modern wars and will play an important role at the beginning or key moment in the wars. To improve the survival captibility of the ballistic missiles, many peneration measures are proposed. Among all these measures, the active decoys have obtained more and more attention because of the high efficiency. As the key sensors in ballistic missile defense (BMD) system, the quality of tracking and discrimination of the radars has a crucial impact on the whole system's performance. Tracking ballistic missiles is the basic and primary task for the radars in BMD, but active decoys bring serious challenges in this area. Researching on the ballistic missile tracking and discrimination can provid the technology support to improve the tracking and anti-deception capability of the radar. Simultaneously, the key algorithm in the platform of the ballistic missile penetration simulation and the theory of the deception jamming optimization can be provided by this researching. So, as an urgent project, deeply researching on this topic has a great military value and reality significance.Taking the request of the researching and development of the missle defence technology as the background, the tracking and discrimination technologies are investigated based on the radar data processing. The investigation includes the ballistic target tracking in midcourse and reentry regime of the trajectory and the discrimination of active decoys by the single radar or the radar network.The midcourse, as the longest and stablest phase in the track, is the most valuable phase for radar tracking. Precisely tracking is the basis for falling point prediction, target recognition, guiding and intercepting. First, necessary and rudimentary background information concerning ballistic tracking is provided. Then, the target dynamics models are derived in four typical coordinate systems (CS). Especially the decoupled explicit equation in non-Cartesian CS is given, which is suitable for EKF directly. The performances of tracking in different CS are compared and summarized, which provides a good basis for further theory and practice research. Finally, an improved algorithm is proposed for ballistic missile tracking in midcourse, which has a better performance than EKF.During the reentry phase, there are two major forces impact on the missile: the gravity and atmospheric drag. If maneuver is presented, a third force—aerodynamic lift force—must be considered. If the maneuver exists, the reentry vehicle (RV) is called ballistic RV (BRV). If the maneuver doesn't exist, it is called maneuvering RV (MaRV). First, aerodynamic forces are described with the concerning of the air density, drag and lift forces. Then, the target dynamics models are derived in four typical CS, and the performance of tracking in different CS are compared and summarized. Finally, with the background of two typical maneuvering reentry trajectories, two kinds of tracking algorithms are utilized and the performances are comparedThe high-fidelity active decoy is a great threat to radar, which can't be filtered or discriminated by radar receiver and signal processing. The theory and technique on active decoy discrimination are proposed based on the radar tracking. The motion model of the active decoy is different from the real target essentially. The dynamic model of the radar filter is generally built based on the real target, so it must be unfit for the active decoy. The unmatchable filter, which is produced by the unfitness, can be utilized to discriminate the active decoy. The quantitative expression of the recessive unfitness and the sensitive measurement of the motive character discrimination are the keys of the discrimination technology. Three methods are proposed based on different characteristics: the trajectory's planarity; the acceleration model; the normalized error. These methods are all based on the target's dynamics characteristic, and made the best use of the radar filtering data. The theory and technique on discriminating active decoy based the dynamics characteristic is great creativeness in the field of electronic counter-countermeasures (ECCM).Radar network can discriminate the high-fidelity active decoy not only based on the target dynamics characteristics but also based on the same-source-testing. The same-source-testing discriminates the active decoys by judging whether the points or filtered trajectories measured by the different radars can be matched or not in the same CS. In the same-source-testing, the measured points are utilized for the centralized radar network, and the filtered trajectories are adopted for the distributed radar network. For the discrimination technology of radar network, the discriminating is coupled with the tracking. Not only the tracking technique is expanded, but also the ECCM is enriched by the tracking and discrimination technologies of radar network.In the last part, the whole dissertation is summarized, the major creativite topices are pointed out and some suggestions for the future work are brought out.The research in the dissertation stems from the request of practical projects and its conclusion and methods are successfully applied in practice and fairly good effects are obtained.