Cross-polarization and size reduction of slotted waveguide array antenna by angled ridges

An ultralow cross-polarization slot array antenna in the narrow wall of ridge waveguide is presented. In the first, a non-angled slot which is created to the narrow wall of ridge waveguide is suggested to be used as radiating resonance slot. The normalized resistance and normalized reactance curves are presented for design purposes. A slot array waveguide antenna was designed using ridges on its narrow wall and six radiation elements having a frequency of 9 GHz by applied the normalized conductance of each radiating slot. It is shown that good performance such as low cross polarization and size can be achieved even for angled ridge in waveguide.