A Low Profile Wideband Circularly Polarized Slotted Waveguide Antenna for W-Band CubeSat Data-Links

Abstract

This article presents a dual circularly polarized slotted waveguide leaky wave antenna for CubeSat communications at W-band. The proposed fully metallic, low profile, and high-performing antenna offers wideband operating bandwidth, which makes it suitable for space applications. To achieve circular polarization, an array of circular holes is perforated at an offset position from the narrow wall of the WR-10 waveguide. The prototype antenna provides a wide axial ratio bandwidth of 13% and an average half-power beamwidth of 4.5° on the elevation plane. At high frequencies, the thickness of the slot affects the emission through the slot, which is not typically encountered at low frequencies. Therefore, to increase the magnitude of the radiated power, the wall thickness of the hole is reduced. The proposed circular hole slotted waveguide antenna design provides superior tolerance, accuracy, and precision compared to any other structures. These characteristics eliminate fabrication challenges, especially within the W-band, and can seamlessly extend into the sub-THz domain as well. The proposed antenna is robust, easy to fabricate, and appropriate for integration into CubeSat. It can be adapted for W-band CubeSat LEO, intersatellite, and constellation missions.