Slotted Waveguide Ka-Band Antenna Fed by a Novel Double Ridge to Single Ridge E-Plane T-Junction

Abstract

This paper presents a slotted waveguide antenna element developed from a single ridge waveguide with a crosssection reduced by 60 % and designed for a fully polarimetric Ka-band airborne synthetic aperture radar system. The center feed required for this particular application is carried out by a novel double ridge to single ridge E-plane T-junction, which distributes the input power symmetrically and with low-losses to both waveguide outputs. The introduced antenna element provides a mechanical robustness desired in airborne applications with low side lobe level and high gain radiation pattern with achieved values of 21 dB and 18.95 dBi respectively. The simulation results shown in this work agree very well with requirements.