A multiband, polarization-controlled energy harvesting metasurface is presented in this article for harvesting electromagnetic energy in the Wi-Fi bands. Inspired by the split-ring resonator (SRR), a metasurface of SRRs is designed by nesting multiple SRRs together. The novelty of the design lies in the controllable multiband polarization and adjustable absorption frequency, so as to achieve the active modulation of energy harvesting on the metasurface at different frequencies. The metasurface is composed of a periodic array of SRRs unit cells, an impedance-matched rectifier, and a load. Metasurface arrays and rectifier integration are proposed to reduce power losses, while the channels formed by the array enhance energy density and improve the ability to capture energy. Moreover, the design for the rectifier is capable of rectifying RF energy from multiple Wi-Fi bands simultaneously at low input RF power density. The finite array of $5\times $ 5 SRRs absorber is fabricated and tested. Measurements in an anechoic chamber show that the fabricated prototype reaches the efficiency of 66.5% at 2.4 GHz, 40.6% at 5.2 GHz, 35.6% at 5.8 GHz under transverse electric (TE) polarization, and 38.3% at 5.3 GHz under transverse magnetic (TM) polarization when the incident power density is greater than 66 $\mu \text{W}$ /cm ² .

A dual-band metasurface array is presented in this paper for electromagnetic (EM) energy harvesting in the Wi-Fi band and Ku band. The array consists of metasurface unit cells, rectifiers, and load resistors. The metasurface units within each column are interconnected to establish two channels of energy delivery, enabling the transmission and aggregation of incident power. At the terminals of two channels, a single series diode rectifier and a voltage doubler rectifier are integrated into them to rectify the energy in the Wi-Fi band and the Ku band, respectively. A 7 × 7 prototype of the metasurface array is fabricated and tested. The measured results in the anechoic chamber show that the RF-to-dc efficiencies of the prototype at 2.4 GHz and 12.6 GHz reach 64% and 55% accordingly, when the available incident power at the surface is 3 dBm and 14 dBm, respectively.

A metasurface array for electromagnetic (EM) energy harvesting for Wi-Fi bands is presented in this paper; the metasurface array consists of a metasurface unit, a rectifier, and a load resistor. Each row of unit cells in the array is interconnected to form an energy transfer channel, which enables the transfer and concentration of incident power. Furthermore, at the terminal of the channel, a single series diode rectifier circuit and a load resistor are integrated in a coplanar manner. It is used to rectify the energy in Wi-Fi bands and enables DC energy harvesting across the load. Finally, a 5 × 7 prototype of the metasurface array is fabricated and measured for the verification of the rationality of the design. Testing in an anechoic chamber shows that the prototype achieves a 72% RF-DC efficiency at 5.9 GHz when the available incident power is about 7 dBm.

This work proposes a polarization-insensitive scalable wide-angle metasurface array for highly efficient ambient energy harvesting in the 5.8 GHz Wi-Fi band. Inspired by dipole antenna principles, we design an asymmetric planar orthogonal dipole-based metasurface featuring monolithic integration of Schottky diodes (HSMS-2860) at unit cell feed gaps. This novel direct-impedance-matching strategy eliminates conventional matching networks, reducing energy conversion losses while enabling 99% radiation-to-AC efficiency across all polarization angles at 5.8 GHz. The coplanar architecture interconnects metasurface unit cells via inductors, simultaneously establishing low-loss DC channels and suppressing RF leakage. Fabricated as a 5 × 5 array, the prototype achieves 77.9% peak RF-to-DC efficiency with polarization insensitivity at an incident power of 25 dBm. Furthermore, with incident powers of 15 dBm and 20 dBm, the proposed metasurface array attained RF-to-DC conversion efficiencies exceeding 40% and 60%, respectively. This result indicates that the array is capable of achieving high energy harvesting efficiency across a broad power range. This scalable, drill-free, and polarization-insensitive design demonstrates strong potential for harvesting ambient RF energy in real-world multipath environments.