Near-Field WPT Using Multisine Phase Alignment and Massive Antenna Array at Extreme Frequencies

We present a novel wireless power transfer (WPT) system targeting indoor Internet-of-things applications within the radiative near-field region at sub-terahertz frequencies. A massive, low-cost transmit array architecture is proposed, with each antenna element transmitting a single tone with phase control to align the tones constructively at a chosen focal point and in time. The primary hardware complexity arises from the required phase control rate, which is directly proportional to either the subcarrier spacing or the transmission bandwidth, and from the requirement for accurate synchronization between transmitted tones. These tones are combined over-the-air, producing a structured impulse-like multisine signal that enhances power transfer efficiency at the intended target. A simplified receive array, composed of antenna elements each equipped with a basic rectifying circuit, receives the transmitted power. Simulation results demonstrate advanced near-field power transfer performance at extreme frequencies due to effective energy focusing, validating the proposed system’s potential for energy-efficient wireless charging within indoor environments.