4× 2-slot element for 30-GHz planar array antenna realized using SIW cavity and fed by microstrip line line-ridge gap waveguide

A 4 × 2 planar rectangular slot antenna array is designed at 30 GHz. The rectangular slots are etched off in the top layer of substrate-integrated waveguide (SIW) Cavity. SIW Cavity fed by a printed feeding network based on the ridge gap waveguide (RGW) technology through a coupling slot. A prototype working at 30 GHz band was designed and simulated. Simulated results show that the prototype achieves a-10-dB impedance bandwidth from 29 to 31 GHz (6.67%). The peak gain at broadside is 13.3 dBi at 30 GHz. The radiation pattern is stable within the operating bandwidth.