Airborne Flexible Rectifying Metasurface System for Wirelessly Powered Unmanned Aerial Vehicles (UAVs)

We present a novel flexible energy harvesting surface, termed the rectifying metasurface system (RMS), designed to wirelessly power unmanned aerial vehicles (UAVs), thereby eliminating the need for periodic battery replacements. The RMS, which is affixed to the aircraft's wings, consists of a metacell array with integrated rectifying diodes. This configuration negates the necessity for additional matching networks. A fatigue reliability analysis confirms that the RMS is robust against airborne vibrations, and its inherent flexibility maximizes radio frequency (RF) energy conversion. Our results demonstrate a remarkable incident angle capture range of up to 75° at a frequency of 5.8 GHz. The RF-to-dc conversion efficiencies reach 59.5% in a flat configuration and 52% when bent, under an incident RF power of 5 dBm. The RMS's design is characterized by its polarization insensitivity and wide-angle reception capabilities, along with efficient conversion efficiency sustained during flight. Owing to its flexibility, lightweight, and high efficiency, the RMS is a promising candidate for UAV-supported wireless power transfer.