Compact inline substrate integrated waveguide filter with transmission zeros

In this paper we propose an inline pseudo-elliptic bandpass filter with three transmission zeros in stopband based on dual-layer substrate integrated waveguide (DLSIW). A new approach which involves utilization of resonating slots in the common wall of stacked waveguides connected in parallel is introduced. Singlet and doublet structures based on hairpin and S-shaped slot resonators are presented as basic units for the modular design of the filter with a non-resonating node.