An inhomogeneous waveguide transformer with hard walls for the excitation of quasi-optical amplifiers

Inhomogeneous waveguide transformers with hard walls are proposed for the excitation of quasi-optical amplifiers. A program based on the mode matching technique is used to analyse inhomogeneous transformers with dielectric loaded waveguide sections. The generalized scattering matrix (GSM) of the whole block is obtained which can be used to predict the fields at the output given the incident excitations. A tapered hard wall horn is replaced with a three section transformer of approximately half the size while maintaining its performance.