Resemblance between gap waveguides and hollow waveguides

There is a lack of suitable numerical ports for the gap waveguides. This study studies the resemblance between the ridge/groove gap waveguide and the conventional hollow ridge/rectangular waveguide, respectively, by using numerical analysis. The dispersion diagrams and characteristic impedances are compared and found to be similar within the stopband of the parallel‐plate modes. Therefore conventional hollow waveguides can be used as ports in numerical analysis of gap waveguides. In addition, this means that the geometry of circuit components in hollow ridge/rectangular waveguides can be used as a good starting point when designing ridge/groove gap waveguide components.