Single ridge waveguide UWB absorbent harmonic filters

Some new types of UWB absorbent harmonic filters are presented in this paper that constructed by a single ridge waveguide and single and/or double series rectangular waveguide loads. These filters are designed by equivalent circuit and analyzed by HFSS. These filters have lower SWR and insert loss in UW pass band, and also have lower SWR and higher isolation in UW stop band. The stop band of the filters mixed with the single and double series loads is wider than that of filters with only single or double series ones.