A Sub‐THz Dual‐Polarized Multi‐Beam Leaky‐Wave Antenna Based on a Meta‐Slot Array

ABSTRACT

This paper presents a leaky‐wave meta‐antenna (LWMA) capable of generating dual‐polarized, high‐gain multi‐beam radiation in the sub‐terahertz (sub‐THz) band. When two guided waves from orthogonal input ports propagate through parallel‐plate metal waveguides and reach the meta‐slot array, they are converted into free‐space radiation via the meta‐slots while undergoing independent phase control. To achieve distinct multi‐beam patterns in two orthogonal polarizations, the Gerchberg–Saxton algorithm is employed to compute the required phase profiles across the radiating aperture, which are implemented by engineering the layout of the meta‐slots. At 0.14 THz, the proposed antenna generates triple beams for x ‐polarization and two beams for y ‐polarization. The simulated peak gains reach 25.5, 25.0, and 25.1 dBi for the x ‐polarized triple beams and 26.1 and 26.5 dBi for the y ‐polarized dual beams, with corresponding radiation efficiencies of 62.8% and 57.9%, respectively. Meanwhile, the cross‐polarization levels are suppressed by more than 24.5 dB, and the isolation between the two polarization channels exceeds −35 dB. A prototype is fabricated to validate the design, and experimental results are consistent with the numerical predictions. By integrating dual‐polarization operation, high gain, and multi‐beam capability, the proposed LWMA demonstrates strong potential for application in 6G communications and sub‐THz detection systems.