Novel Dual-Band Phase-Gradient Metascreen and Dual-Band Near-Field Meta-Steering Antenna

This article proposes first of its kind novel dual-band near-field meta-steering (DB-NFMS) antenna operating in a full duplex in the Ku-band. The antenna is developed using an entirely new dual-band phase-gradient metascreen (DB-PGM), which is synthesized to simultaneously provide the required phase gradients at the two operating frequencies. A novel characteristic of the metascreen includes a fundamental cell, which has slot-based fully metallic architectures with high structural integrity and low fabrication complexity that simultaneously allow independent radio-frequency (RF) transmission in dual bands. The elimination of dielectrics reduces the cost and expands their usage to even extreme conditions, such as high-power and space applications. Additionally, the DB-PGMs are polarization-insensitive and can be made out of cheap, off-the-shelf metal sheets. A prototype is made, and its dual-band beam-steering principle is verified numerically and experimentally. Irrespective of the rotation of the DB-PGMs, the measured impedance bandwidths of the antenna system at VSWR < 2 are around 400 MHz (11.57 – 11.97 GHz) and 1050 MHz (13.95 – 15.0 GHz). Within the maximum scan loss of 3 dB, the measured simultaneous beam-steering angles in the elevation plane are ±46° and ±51° at f _L and f _H , respectively, with a full 360° steering in the azimuth. The respective total weight and thickness of each DB-PGM are 68.8 g and 18.4 mm (0.72λ _L ). Including feed, the overall antenna profile is only 52.8 mm (2.1λ _L ).