Propagation Characteristic Analysis Of Guided Wave Structures With 1D Inhomogeneous Dielectrics

To satisfy the requirement of modern and future microwave systems for miniaturization,as a practical device in microwave systems,the guided wave structure plays a very important role in miniaturization.Throughout the development history and tendency of the miniaturized guided wave structures,introducing one-dimensional(1D)inhomogeneous dielectrics or composite left-/right-handed dielectrics into the guided wave structures influences the realization of the miniaturized guided wave structures.The precondition of realizing miniaturized guided wave structures is to acquire the propagation characteristics of the electromagnetic wave in these structures.In order to accurately analyze the wave propagation in guided wave structures,the Rayleigh-Ritz method has been used to analyze the propagation characteristics of the guided wave structures with 1D inhomogeneous dielectrics and composite left-/right-handed dielectrics.The main contributions and innovations of this dissertation can be summarized as follow:(1)To accurately analyze the propagation characteristics of guided wave structures with 1D inhomogeneous dielectrics,it has been found that the Rayleigh-Ritz method is suitable to analyze the guided wave structures with simple geometry structures and complex dielectric distributions throughout the summarization and the research on the electromagnetic calculation methods of the guided wave structures.Thus,the Rayleigh-Ritz method has high potential to study the propagation characteristics of the guided wave structures containing 1D inhomogeneous dielectrics.The Rayleigh-Ritz method has been used to solve the propagation characteristics of rectangular metallic waveguides filled with 1D inhomogeneous dielectrics,and the calculation results have been compared with those in literature,showing the accuracy of the Rayleigh-Ritz method.It provides a feasible solution for the analysis of propagation characteristics of circular metallic waveguides and cylindrical dielectric waveguides with radially inhomogeneous dielectrics.(2)In this dissertation,the Rayleigh-Ritz method has been used to solve the propagation characteristics of three kinds of circular metallic waveguides filled with radially inhomogeneous dielectrics,including circular metallic waveguides filled with radially graded dielectrics,circular metallic waveguides filled with multilayer homogeneous dielectrics and circular metallic waveguides lined with radially graded dielectrics.The accuracy of the Rayleigh-Ritz method has been verified by comparing the results with those obtained by the matrix method.The influence of radially inhomogeneous dielectric distributions on the propagation characteristics of circular metallic waveguides has been analyzed.(3)In this dissertation,the Rayleigh-Ritz method has been used to solve the propagation characteristics of three kinds of radially inhomogeneous cylindrical dielectric waveguides:radially graded cylindrical dielectric waveguides,radially multilayered cylindrical dielectric waveguides and multilayered cylindrical dielectric waveguides with radially graded dielectrics.The accuracy of the Rayleigh-Ritz method for analyzing the propagation characteristics of radially inhomogeneous cylindrical dielectric waveguides has been verified by comparing the calculation results with those obtained by the matrix method.The influence of radially inhomogeneous dielectric distributions on the propagation characteristics of the cylindrical dielectric waveguides has been analyzed.(4)The above-mentioned studies provide theoretical basis and technical support for the analysis of the propagation characteristics of guided wave structures with composite left-/right-handed dielectrics.In this dissertation,the Rayleigh-Ritz method has been used to solve the propagation characteristics of the rectangular metallic waveguides filled with composite left-/right-handed dielectrics.The differences of propagation characteristics between rectangular metallic waveguides filled with composite left-/right-handed dielectrics and rectangular metallic waveguides filled with right-handed dielectrics have been analyzed.The influence of 1D inhomogeneity of composite left-/right-handed dielectrics on the propagation characteristics of rectangular metallic waveguides has been analyzed.The research on the propagation characteristics of rectangular metallic waveguides filled with composite left-/right-handed dielectrics provides a feasible support for the subsequent research on the propagation characteristics of circular metallic waveguides and cylindrical dielectric waveguides with composite left-/right-handed dielectrics.