A highly efficient, scalable, tetra-band metamaterial-based ambient RF energy harvester

This paper presents an innovative metamaterial-basedradio frequency (RF) energy harvesting system designed toefficiently capture ambient RF energy across multiple frequencybands, including Wi-Fi (2.45 GHz) and 5G (0.9 GHz, 1.8 GHz,2.1 GHz). Utilizing electric inductive-capacitive resonators anda rectification circuit, the system converts ambient RF energyinto direct current (dc) power with high efficiency. Specifically,a single unit-cell of the proposed 8x8 harvester is capable ofgenerating up to 562 μW under an RF ambient power densityof 40 μW/cm². This high efficiency and scalability make it idealfor powering low-power Internet of Things (IoT) devices andsensors. The design emphasizes optimizing the unit-cell to minimize computational complexity, enabling a more straightforward and scalable implementation. Experimental results demonstrate the system’s ability to efficiently harvest RF power across the specified bands, validating its potential as a sustainable solution for the growing power demands of IoT networks.