Simultaneous Near-Field and Far-Field Wireless Power Transfer Using Single Antenna

This paper presents a novel energy transfer system capable of operating simultaneously in both near-field and far-field modes. The system’s rectifying antenna leverages a structurally sharing design, enabling dual functionalities within a single-arm spiral antenna. On one hand, the antenna functions as an NFC coil antenna, supporting NFC communication and near-field energy harvesting at 13.56 MHz. On the other hand, it operates as a single-arm helical antenna at 2.45 GHz, enabling ambient energy harvesting from the Wi-Fi frequency band. The innovative shared-aperture design minimizes the need for additional components, ensuring compactness and reducing system complexity. Furthermore, the design overcomes the traditional limitations of separate antennas for near- and far-field operations, offering a more integrated and space-efficient solution.