Orbit Design for a Satellite Swarm-Based Motion Induced Synthetic Aperture Radiometer (MISAR) in Low-Earth Orbit for Earth Observation Applications

Soil Moisture and Ocean Salinity mapping by Earth observation satellites has contributed significantly toward a better understanding of the system, such as its hydrosphere or climate. Nevertheless, an increased spatial resolution below 10 km with radiometric in range 2 K–3 K data could yield more complete picture global hydrological processes climate change. Operational radiometers, SMOS, have already approached prohibitive sizes for spacecraft due to required large antenna apertures. Therefore, radiometer concepts based on number flying close proximity (swarms) been proposed possible solution. This article investigates orbit mechanics placing satellite swarm-based motion induced synthetic aperture (MISAR) low applications. The synthesis array is formed individual antennas autonomously controlled nanosatellites (deputies) correlator Y-configuration carried chief satellite. design methodology optimization positions within plane subsequent translation coordinates into initial conditions general circular orbits (GCOs). enables computationally efficient ensures time invariance response. Based this methodology, simulations performed swarms consisting up 96 satellites. Simulations show that can be less than applications where requirements sensitivity are relaxed ( $\Delta T\sim 3$ K).