On edge diffraction rays of an open-ended waveguide

Two main results are reported in the development of a system of rays diffracted at the edges of an open-ended parallel-plate waveguide which take care of the coupling effect between the two plates of the waveguide automatically. As an example, the application of such rays to the problem of radiation from an open-ended waveguide recovers the exact solution obtainable by the Wiener-Hopf technique.