Metasurface Antennas for Synthetic Aperture Radar

Synthetic aperture radar offers unparalleled satellite imaging capabilities for planetary observation. Future systems will realize high resolution with near-real-time revisit rates by using coordinated satellites, but their development has been slowed by the high cost, high power draw, and substantial weight associated with existing antenna technology. Metasurface antennas - a lightweight, low cost, and planar alternative - can address these challenges to make large scale, multi-satellite systems practical. In this work, an electronically steered metasurface antenna prototype is developed for synthetic aperture imaging. A cohesive approach to modeling and design led to a Nyquist sampled layout which minimizes inter-element coupling and suppresses grating lobes. Experimental measurements validate its ability to steer a beam in 2D across a wide bandwidth. Robust performance and favorable hardware characteristics have poised metasurface antennas to affect many microwave industries and to facilitate multi-satellite constellations for spaceborne synthetic aperture radar.