6 GHz to 40 GHz CubeSat Radiometer Antenna System

A 6–40 GHz antenna system for the CubeSat Radiometer Radio Frequency Interference Technology Validation mission is presented. The antenna system includes three bottom-tapered helical antenna elements that cover 6–12, 12–22, and 22–40 GHz, respectively. The design procedure for achieving continuous gain coverage versus frequency from 7 dBic at 6 GHz to 21 dBic at 40 GHz is discussed. The helical antenna elements are supported by a carefully designed meshed radome made of 1 mm-thick Ultem 1000 material for minimizing impacts to antenna performance. The entire antenna system has a volume of 2 cm (height) $\times7.3$ cm (width) $\times25$ cm (length), or 365 cm3, which is less than 0.5 U (500 cm3). The total mass of the antenna payload is 116 g. Comparisons between the simulation and measurement performance show good agreements. The final fabricated antenna/radome payload also passed typical CubeSat temperature, vacuum, and vibration requirements and was successfully deployed in space in August 2018.