Angular and Radiometric Resolution of Y-Shaped Nonuniform Synthetic Aperture Radiometers for Earth Observation

MIRAS is the single payload of the European Space Agency's Soil Moisture and Ocean Salinity (SMOS) satellite mission, and it will be the first synthetic aperture radiometer for Earth observation from space. It consists of an array of 69 antennas uniformly spaced along three arms forming a Y-shaped antenna array. This work analyzes the angular resolution improvement, and the radiometric performance degradation when the spacing between antennas is geometrically increased.