An absorption resonance method for measuring mode conversion coefficients of overmoded waveguide components†
R. G. Meadows · International Journal of Electronics · 1973
A method for measuring the mode conversion coefficients of overmoded rectangular waveguide components utilizing trapped-mode absorption resonance phenomena is described. The mode conversion coefficients are deduced from transmission and reflection coefficient measurements made at the output and input of a simple overmoded system which consists of We taper transitions from single to overmoded guide, the test component and lengths of overmoded guide. The insertion loss of the component with respect the H10 mode, and the higher order mode suppression produced by the inclusion of a mode filter in the system may also be measured. Approximate estimates of higher-order mode attenuation coefficients may also be ascertained.