Single-Layer Sequential Rotation Network in Gap Waveguide for a Wideband Low-Profile Circularly Polarized Array Antenna

A low-profile circularly-polarized sequential rotation fed 4 x 4 array antenna working in the Ka-band from 27.5 GHz to 31 GHz is presented. The particularity of the antenna lies in its single-layer sequential rotation feed network implemented in a bed of nails using a combination of groove and ridge gap waveguides. The basic radiating element is one slot loaded by a simple coffee-bean-shaped parasitic element on top. Experimental results show an antenna matching below -10 dB in a 13.6% bandwidth and a measured axial ratio below 1.3 dB in the desired band.

Automated summary

This study presents a low-profile circularly-polarized sequential rotation fed 4x4 array antenna that operates in the Ka-band. The antenna features a single-layer sequential rotation feed network implemented using a combination of groove and ridge gap waveguides. Experimental results demonstrate that the antenna has a matching below -10 dB and a measured axial ratio below 1.3 dB in the desired band.