Highly Efficient Wideband mmWave Rectennas for Wireless Power Transfer System With Low-Cost Multinode Tracking Capability
Chaoyun Song, Lei Wang, Ping Lu, Cheng Zhang, Zhensheng Chen, Xuezhi Zheng, Yejun He, George Goussetis, Guy A. E. Vandenbosch, Yi Huang
Abstract
An innovative wireless power transfer (WPT) system utilizing millimeter-wave (mmWave) power for multinode charging and tracking is presented in this article. The core concept of the system revolves around the utilization of frequency-dispersive leaky-wave antenna (LWA) transmitters, enabling passive beam scanning in the far field without the need for active phased arrays. However, such a system requires a breakthrough in receiving rectenna design at mmWave frequencies, encompassing a wide frequency bandwidth, wide beamwidth, and high RF-to-dc conversion efficiency beyond 20 GHz. In this work, we introduce a pioneering mmWave rectenna design achieved through the codesign integration of a magnetoelectric (ME) dipole and high-frequency diodes, eliminating the need for complex impedance matching networks at mmWave frequencies. The proposed rectenna operates in the frequency range of 24–34.5 GHz, achieving over 50% RF-to-dc conversion efficiency for input powers exceeding 15 dBm. In addition, the rectenna demonstrates improved gain and beamwidth compared to conventional designs, enabling wide-angle reception of frequency-scanning passively beamformed mmWave signals. A practical demonstration of the proposed system showcases simultaneous wireless charging of three nodes, highlighting its notable advantages in terms of mobility, cost-effectiveness, and simplicity over conventional WPT technologies.