Numerical solution of waveguide-discontinuity problems

A method for the solution of waveguide-discontinuity problems using a digital computer is described, and examples are given to illustrate possible applications. For the method to be applied, the discontinuity must lie entirely in a surface transverse to the direction of propagation, and various techniques are described for treating planar discontinuities. Examples include a change in waveguide cross-section and a change in the cross-section of a dielectric contained within a uniform waveguide. Favourable comparison is made with experimental results and alternative theoretical results, where these are available. Virtues of the method are simplicity and the ease with which discontinuity problems in overmoded waveguides may be treated.