High Frequency Electromagnetic Scattering Modeling And Its Application

The electromagnetic (EM) scattering features of target and environment are one of the most important and essential resources for the martial information, and EM modeling is an important mean to obtain these features. Compared with the numerical method, high frequency method has the dominant advantages of clearer physical meaning and higher efficiency for the computation of EM scattering feature of electrically large complex target. Concerning the fast, efficient and accurate modeling of radar cross section (RCS), wide-band radar echo and radar target glint in actual engineering application, the key technique, realization and the applicability of high frequency method are studied by the numbers in this paper.Firstly, the status quo of numerical method, time and frequency domain high frequency methods, and computation of angular glint is summarized, and the applied fields and problems to be solved of EM modeling are presented.Concerning the engineering need of geometrical modeling, the CAD modeling method of complex target and the creating and handling techniques of the mesh based on the triangle plates and the parametric curved surfaces are studied, and the merits and demerits of these methods are compared.Aimed at the computation of scattering for the electrically large complex target, the theory and realization of high frequency method, including the computation and implementation of primary and multiple reflections, and diffractions, the region projection method based on polygon model, and physical optic (PO) method based on NURBS parametric surface model, is studied. Furthermore, the scope of application and the practical aspect of these methods are analyzed in detail.Concerning the fast computation of wide-band RCS for radar target and real time simulation of wide-band radar echo, the time domain high frequency method is researched. Furthermore, a high efficient method based on short pulse equivalence and subsampling acceleration is presented. For the computation of the complex target angular glint, the gengral formulaes of phase gradient method (PGM), poynting vector method (PVM) and monopulse radar angular glint base on angular measurement theory is deduced base on electromagnetic scattering theory. The polarization effect of the receiving antenna is firstly introduced into the PVM for angular glint computation to consummate three methods are compared and alalyzed.Two software suits, radar target signature prediction system and drones features analyzing system, have been developed by integrating all the theory mentioned above. The basic function, considerations in design and some example abe briefly introduced. At present, the software suites have been applied and verified in engineering practice.Finally, all works mentioned above are concluded and future researches are also addressed.