A 24-GHz 4-Element Multi-Beam Wireless Energy Harvesting Array with Class-F Rectifiers Achieving 51.5% PCE

This paper presents a 24GHz 4-element concurrent multi-beam energy harvesting array. The proposed architecture introduces three-line-couplers as the matching network to develop class-F waveforms and achieve 51.5% rectifier power conversion efficiency (PCE). A 4-port Butler matrix with transformer-based 90° hybrid couplers is utilized to perform concurrent coherent beamforming. Implemented in a 22nm CMOS FD-SOI process with a total core area of 0.53mm2, the proposed array can cover the full field of view (FoV) with 28dB peak-to-null ratio and 30.2% system efficiency.