Enhanced Near-Field Power Beam Scanning in E-Plane and H-Plane Using mmWave Leaky-Wave Antenna

This paper presents a two-dimensional (2-D) near-field–focusing (NFF) leaky-wave antenna (LWA) array formed by stacking 16 one-dimensional (1-D) NFF LWAs with 5.45 mm spacing and element-dependent feed phases. The derived aperture phase distribution is obtained from the finite-distance path-length condition, and applied as element-dependent feed phases. The proposed excitation synthesizes a converging aperture field that produces a compact focal spot with a 6 dB power-density enhancement compared with a conventional far-field focusing (FFF) configuration at the same distance. While the NFF design exhibits a lower far-field gain (18.4 dBi) than the FFF case (23.9 dBi), it still maintains strong directional radiation and stable far-field characteristics. This demonstrates that NFF and high-quality far-field performance can be simultaneously achieved. The resulting dual-function aperture is well suited for wireless power transfer and communication applications, offering a compact and efficient solution for simultaneous wireless information and power transfer (SWIPT) systems.