Dual‐band bandpass filter with high selectivity based on 3D printable groove gap waveguide.

A compact dual‐band bandpass filter (BPF) with high selectivity based on 3D printable groove gap waveguide (GGW) for millimeter application is proposed by the authors. Two stacked dual‐mode GGW resonant cavities including TE102 and TE201 are used to realise a compact structure. The dual‐band bandpass response of the GGW BPF is developed from a split‐type coupling topology which produced two transmission zeros (TZs) between the two passbands. In addition, two TZs are generated outside the two passbands after introducing a source‐load coupling, which achieves a higher frequency selectivity. For verification, a prototype is designed, fabricated and measured. The measured results agree well with the simulated ones, which validates the proposal. [ABSTRACT FROM AUTHOR]