Analysis And Research On Electromagnetic Characteristic Of Metal-Medium Carrier Based High Frequency Method

With the continuous development of communication technology, electronic communication equipments which structure is more complex constantly improve the function, the range of frequencies is gradually toward the high frequency in the fields of electromagnetism such as communication, radar. Therefore, the research on electromagnetic characteristic of electrically large size target has very important significance. The results of the full wave method are accurate. But it has defects such as low computational efficiency, high computer resource usage, etc., when using it to analyze electrically large object. As the important algorithm of electromagnetic scattering and radiation problems, the high frequency algorithm which has been a major mean that is widely used in analysis of electrically large problems has advantages such as low computer resource usage, fast computational speed. In this thesis, compared with the full wave method, the accuracy and applicability of the high frequency method are discussed. The application of the algorithm in analyzing radiation and scattering problems are studied.Firstly, the basic principle of physical optics method are introduced. Some practical examples are simulated by physical optics method. The accuracy of physical optics(PO) is validated through comparing with MLFMM. Dielectric physical optics is deduced on the basic of high frequency scattering mechanism. This method has high engineering value.Secondly, in order to combining with the above method, the excitation source should be dealt when analyzing electromagnetic characteristic of radome, lens antenna, etc. The treatment of the excitation source is introduced in the thesis. Plane wave spectrum(PWS) and aperture integration(AI) are introduced to deal with the excitation source. The correctness of the method and the ability combining with high frequency method to deal with engineering problems are verified by comparison and analysis.Finally, in this thesis, the accuracy of this method is verified by a large number of typical engineering examples. In order to show the computing capacity, the simulation results of reflector antenna, radome, Fresnel zone plate antenna and the airplane model are discussed. The analysis of a series of numerical examples further highlights the engineering value of this algorithm.