A Ka-Band Spaceborne Synthetic Aperture Radar Instrument: A modular sparse array antenna design

The article presents the design of a Ka-band synthetic aperture radar (SAR) instrument based on innovative phased-array antennas, with steering capability in azimuth and elevation. To limit the complexity and costs associated with conventional large active arrays with regular layouts, a sparse array concept is presented. The proposed approach results in a 40% reduction in the number of active controls, with a marginal reduction in performance compared to conventional phasedarray solutions previously developed for SAR instruments. Additionally, a preliminary thermomechanical design is presented to assess the challenges associated with the industrial production and to identify options for accommodation on the spacecraft.