Ballistic Missile Target Electromagnetic Scattering Computation

Ballistic missile defense is an important task of air defense warning under the conditions of modern warfare. and radar-based target recognition technology is the core of the ballistic missile defense. Because of its unique military background, it is difficult to get the measured data of the target which are focused in the process of penetration. Therefore, the simulation of electromagnetic scattering data become an important source of data for recognition technology research.With the help of the software of FEKO. After analyzing the electromagnetic scattering mechanism of the ballistic missile targets. According to the electrical size and the details of the structure of the targets. Various electromagnetic scattering calculation methods have been used to achieve the best balance between the computational efficiency and the accuracy.Firstly. The penetration characteristics of the Minuteman III ballistic missile are analyzed. The three-dimensional model of the targets are established. Such as warheads, conical light bait, the cone-shaped re-bait, spherical light bait, envelope ball and the post boost vehicle, The material composition of the targets are analyzed. the relationship between the mesh size of the target model and the computation time are analyzed.Secondly, after analyzing the mathematic principle of various algorithms, According to the complexity and the electrical size of the targets, We adapt the compatible algorithm to calculate the different model. The large electrical size targets of flat surface are calculated by the physical optics, the medium electrical size targets are calculated by the multilevel fast multi pole algorithm, the method of pre-conditions, convergence precision, most thin-layer box the size were used to accelerate the convergence. The method of symmetry, parts decomposition, Interpolation are used to reduce the number of the Surface element and the number of unknown quantities. with the target of Small electrical size, we use the method of moments.Finally, according to the principle of the pulse radar and the pulse compression, the scattered field value corresponding to the frequency point which have been computed from sampling point in the single pulse by FFT are calculated. The Scattered field data are processed by the method of matched filter. Ultimately, We get one-dimensional distance image of targets. The research of this subject provide simulation data for the work of target detection and tracking, feature extraction and target recognition.