Waveguide Junction Analysis Involving Asymmetrical Modes

摘要

A modal expansion technique is applied to a system of uniform waveguides interconnected by abrupt junctions. Computer codes developed for the asymmetrical modes on-axis transition and all modes off-axis transition have been tested and verified through two separate experimental verifications. The three main parts of this work are: (a) The tentative formulation for an abrupt transition from one waveguide to another, where each junction is restricted to having only one input and one output waveguide, while a conducting wall on each side of the junction is accounted for, (b) The development of convergence criteria for the selection of the important modes via symmetry used in each waveguide section, and (c) The numerical implementation of the evaluation of the coupling coefficients for the coupling cases: On-axis asymmetrical modes (circular to circular, circular to coaxial, and coaxial to coaxial waveguide transitions). Off-axis for all modes (circular to circular, circular to coaxial, and coaxial to coaxial waveguide transitions). The implementation of this formulation requires modification of the structure of the matrix equation of the existing code. To expand the capability and the versatility of the code, future work should include the implementation of ridged waveguide, dielectric loaded waveguide, and multiport junctions. (Author)