Research On Transmission Characteristics Of Ridge Waveguide In Deformations By The Finite Element Method

Ridge waveguides have been widely studied in conjunction with microwave andmillimeter-wave applications because of their unique characteristics, such as low cutofffrequency, wide bandwidth and low impedance characteristics. In recent years, so that theridge waveguide components has been widely used in radar, communication systems andmicrowave information processing. The problem of analysis transmission characteristics ofridged waveguide is one of the practical problems in Microwave Theory and Technology, it isthe foundation of design microwave transmission line and waveguide components.Finite element method is a numerical technique for solving numerical solution ofdifferential equations and integral equations. This method is based on variational principle，itis able to solve most of the physical and engineering problems effectively.The cutoff wavelength, single-mode bandwidth, attenuation constant, power capacity andthe characteristic impedance of waveguide are important parameters of transmissioncharacteristics, and it is an important indicator to measure the transmission performance. Inview of various deformations of ridge waveguide devices in production, assembly and use,the paper adopts the finite element method in the Matlab environment to research theinfluence of displacement distortion and distortion under stress on transmission characteristicof rectangular single-ridge waveguide and trapezoidal single-ridge waveguide. Programmingis achieved to perform the meshing to cross-section of ridge waveguide, numerical computingand data processing. And give out the variations of characteristic parameters with the ridgedimensions for different values of the relative permittivity and the degree of deformation. Thecore content of this paper is divided into two parts, namely, the effect of deformation ontransmission characteristics of the unfilled ridge waveguide and dielectric loaded ridgewaveguide.Numerical results indicate that the deformations makes the characteristic attenuation ofunfilled ridge waveguide increase, the power-handing capability and impedance decreased,lateral deformation has bigger influence on characteristic attenuation of ridge waveguide,which is primarily because of the field distribution of the ridge waveguide that mainlyconcentrate on the center position of ridge, and lateral deformation has greater impact on thefield distribution, therefore, lateral deformation greatly affects transmission parameters of theridge waveguide. For the dielectric loaded ridge waveguide, the cutoff wavelength,attenuation, power handing capability and impedance are considerably increased byincreasing permittivity, single-mode bandwidth decreases continuously with permittivity.Similar to unfilled ridge waveguide, it has bigger influence and should be respected in use that lateral deformation on dielectric loaded ridge waveguide.