Couplings in Direct-Coupled Waveguide Band-Pass Filters (Correspondence)

Couplings in direct-coupled waveguide band-pass filters can be described in two different ways. Cohn describes couplings in terms of normalized susceptances of the coupling circuit elements (e. g., posts or irises ). Dishal describes interstage couplings in terms of a coefficient of coupling between adjacent resonators. Although Cohn has briefly mentioned coefficients of coupling in his paper, the interchangeability of the two methods of describing the couplings has not been clearly established.