CubeSat Formation Antenna Array Synchronization for GNSS-R

This paper presents an approach to improving GNSS-R Earth observation resolution. The proposed method involves using a large antenna array comprising CubeSats flying in formation to synthetically increase the aperture. The paper discusses how the orbital constraints necessitate changes to the formation over time and require the formation plane to be inclined relative to the Earth's surface. The study examines a 1 km resolution target, side lobe level restrictions, and the isotropy of the ground spot. Synchronization challenges are explored by characterizing an antenna array involving CubeSat prototypes.