A Compact 118-GHz Radiometer Antenna for the Micro-Sized Microwave Atmospheric Satellite

A linear polarized 118-GHz antenna is designed for a radiometer payload hosted aboard a 3U atmospheric CubeSat. The radiometer antenna is a horn-fed offset parabolic reflector. The antenna has a maximum +37 dBi realized gain, 2.4 ° half-power beamwidth, and a minimum 95% beam efficiency within the operational bandwidth. The antenna is compact, meeting the MicroMAS mission requirement for a highly integrated and ultra-compact radiometer. CubeSats present stringent size/volume and weight constraints on overall component design. We present our design, along with simulated and measured results, that meet the size/volume, weight, and electrical requirements for the radiometer antenna and comply with CubeSat standards.