High Frequency Method Of Target Electromagnetic Scattering Based On Equivalent Medium Theory

Since the advent and continuous development of radar,the calculation and analysis of electromagnetic scattering characteristics of complex targets has been an important research direction in the electromagnetic field.In the analysis of the electromagnetic scattering characteristics of large targets,the high frequency method has the characteristics of simple calculation algorithm,fast calculation rate and small computational memory.Therefore,compared with the numerical method,the high frequency method is more suitable for the calculation and analysis of large targets with its unique advantages.The main research contents of this paper are as follows:(1)this paper expounds the definition of Radar Cross Section,analyzes the advantages and disadvantages of various electromagnetic scattering calculation methods and the research status at home and abroad,introduces the basic concepts of physical optics method and bounce ray method,and deduces the detailed calculation process,laying a theoretical foundation for calculation research.(2)for large targets with medium,the electromagnetic scattering characteristics are calculated by combining the theory of equivalent medium with the high-frequency method.For the electromagnetic modeling of the medium part,the equivalent medium theory is used to treat the medium part,and the non-uniform or multi-layer medium is equivalent.to the single-layer uniform medium by parameter inversion,which simplifies the modeling and calculation process.(3)aiming at the shortcomings of the physical optics method in the calculation process,the edge diffraction theory is introduced to improve,and the contribution of edge diffraction to the electromagnetic scattering of the target is added on the basis of the calculation results of the physical optics method,so as to improve the accuracy of the calculation.The RCS of the dielectric part is calculated by the electromagnetic scattering method of the dielectric surface element.Amodel example is set up and a series of models are calculated and analyzed by the method of this paper.The high-frequency method based on the equivalent medium theory proposed in this paper has been integrated into an electromagnetic computing software,including geometric modeling of the target,electromagnetic modeling and post-processing modules,which can be used to study the scattering characteristics of the target and stealth technology.