The transformation of admittance through a matching section and lossless waveguide junction

The paper describes a method of setting up a matching section, comprising a variable reactor and phase shifter, in cascade with a lossless waveguide junction to obtain a particular admittance transformation. The terminal planes are defined by the position of voltage zeros when the junction is terminated by a short-circuit. The matching section and junction are regarded as two junctions in cascade and, using conventional theory, the relation between the admittance transformation parameters and input-voltage reflection coefficients is derived. Some experimental results obtained using an S-band waveguide system are quoted to demonstrate the application of the theory.