Analysis For Transmission Characteristics Of Ridged Waveguides With Complicated Structure By Using Fourier's Expansion-Differential Method

In order to meet some requirements in microwave transmit systems, it needs to research some new waveguides with especial sections. Ridged waveguides with complex sections have some especial characteristic because of loaded ridges. So, we can strengthen its application if they are solved accurately. Fourier's Expansion-Differential Method (FEDM) has many advantages such as simple derivation, clear expression, less computation quantity and universal adaptation, etc. So it was applied widely since 2002. The transmission characteristics of ridged waveguides with complicated structure and waveguides with inhomogeneous dielectric are studied and analyzed by using FEDM in this paper. Through analyzing the errors of the numerically calculating results for the cut-off wave numbers or characteristic equations of symmetrical single ridged waveguides, the correctness of the analytic model in this paper is testified. In addition, the transmission characteristics of dissymmetrical single ridged waveguides, symmetrical single bridged waveguides with inhomogeneous dielectric, millimeter-wave quadruple ridged square waveguides, new type of single V-ridged, dual-V ridges waveguides and parabola-ridges waveguides presented in this paper are analyzed and studied as well. The result show that the electromagnetic field has been strengthened and it has some especial characteristic contrast with regular waveguides because of loaded ridges, such as their cut-off wavelength changes longer when loaded dipper ridges. When the depth of ridge is certain, existing a ridge width which cut-off wavelength is longest .The dispersion characteristic becomes better for the ridges and the bandwidth becomes wider along with the ridges' depth. More, the dispersion characteristic is better, the cut-off wavelength is longer when loaded inhomogeneous dielectric in ridge area, etc.Just because of their characteristic of the ridged waveguides, they can be applied universally in region of microwave systems, millimeter waves systems and electronic devices, such as applied in optical broad-band modulation, mixing circuit and used to design ridges waveguide slot array antennas or dual-polarized broad-band horn antennas, etc. It is shown that the method is convenient, effective, universal and higher compute precision in solving the problems of ridged waveguides. So the analysis result has certain referenced values for waveguide theory and practical engineering applications.