Fast Analysis Of Electromagnetic Scattering Characteristics Of PEC Targets Based On Compressed Sensing Theory

The study of electromagnetic waves has become an important research direction with the deep application of electromagnetic equipment in people's life since the twenty-first Century.Scientific experiments,theoretical analysis and high performance computing are three main research methods on a variety of issues in modern scientific research.Computational electromagnetics which is specifically for electromagnetics has become an effective method to solve the complex problem of electromagnetic field and microwave.For example,we can get electromagnetic scattering properties of target by actual measurement,but this method needs ideal test environment,expensive equipment and reliable testing methods.These requirements are not only time-consuming and laborious,but also sometimes unable to meet.But we can get electromagnetic scattering properties of target by numerical method.However,numerical methods are not perfect.Numerical methods need a lot of time when dealing with complex electrically large problems.Therefore,the research and improvement of the existing numerical methods have become one of the key goals of computational electromagnetics.How to obtain a stable and efficient numerical method not only has the significance of theoretical guidance,but also has the value of practicalapplication.Method of moments is one of the most frequently used methods in practice in these numerical methods.However,it is difficult to solve the matrix equation when analyzing the electromagnetic scattering problem of the electric large target.This thesis studies the method of accelerating method of moments by compressive sensing,and applies it to the solution of the electromagnetic scattering properties of the conductor.This method improves the computation efficiency of the method of moments.This thesis first introduces the basic theory of method of moments and compressive sensing,including the establishment of electric field integral equation,the principle of method of moments,the basis function and weight function,the theoretical framework of compressed sensing,the sparse basis,the observation matrix and the recovery algorithm.Then,we apply this method to method of moments of 2-D conductor targets,and discuss the influence of different sparse basis and recovery algorithm on recovery effect.The application of compressed sensing need to know the sparse basis of the current in advance,but the induced current of 3-D target which expressed by RWG basis function is not sparse on commonly used sparse bases.To overcome this problem,a method of combining compressed sensing with characteristic basis functions is proposed to analyze the electromagnetic scattering problem of 3-D conductor targets in this thesis.The results of the numerical experiments verify the reliability and efficiency of this method.Finally,this method is analyzed and summarized,and the future direction is predicted.