Radar in a CubeSat: RainCube

CubeSats are strong candidates for Earth Science mission and the need for a high‐gain antenna is crucial. The radar in a CubeSat (RainCube) mission, developed at NASA's Jet Propulsion Laboratory and launched in 2018, is a 6U. This chapter offers a detailed state of the art of deployable antennas for CubeSat with a focus on mesh deployable parabolic antennas. It provides the basic knowledge required to design focal‐fed reflectors and dual reflector antennas (i.e. Cassegrain and Gregorian reflectors) as this is essential to understand how the RainCube antenna engineers converged into the final design. Analytical and experimental results are provided showing excellent agreement. RainCube is a proposed technology demonstration mission to enable Ka‐band precipitation radar technologies on a low‐cost, quick‐turnaround platform. The chapter also provides a brief description of the S‐band and UHF telecommunication capabilities.