Low-Cost 1-D Beam-Steering Reflectarray with ±70° Scan Coverage

In this communication, a novel low-cost reflectarray mechanism combining feed displacement and reflectarray panel in-plane rotation is introduced to realize 1-D ±70° beam scan coverage. A subwavelength multi-resonance reflectarray element is designed to suppress the grating lobe and provide an adequate phase range over 360°. The spatial-domain phase matching method (PMM) is applied in the wide-scanning reflectarray synthesis process. Meanwhile, effects of both incident and reflection angles are taken into consideration during the optimization. A 640-element mechanical beam-scanning reflectarray operating at 12 GHz has been designed, analyzed and fabricated. The measured gain of the designed reflectarray is 26.2 dBi at 12 GHz when the main beam scans to the broadside direction, corresponding to an aperture efficiency of 42.5%. Meanwhile, the measured gain variations of the designed reflectarray are 3.1 dB and 4.9 dB for scan ranges of ±60° and ±70°, respectively. The lost-cost wide-scanning characteristic of the designed reflectarray makes it suitable for many applications, especially commercial tracking platforms.