Metasurface based antenna array with improved performance for millimeter wave applications

Abstract

This article presents an efficient ultra-miniaturized metasurface-based antenna array with high gain and wider bandwidth for millimeter-wave applications. The presented 1 × 2 compact array incorporates two patches with rectangular slots for gain, impedance matching, and bandwidth enhancement. Further performance is improved by designing a single-layer compact reflecting metasurface with a 2 × 4 array of diamond-shaped split-ring unit cells, where each unit cell has a compact size of only 1.35 × 1.35 mm2. A Fabry–Perot cavity is created by positioning this metasurface at approximately 0.5 λ0 (where λ0 is the wavelength in millimeters) above the antenna array. This integration allows for improved performance and reduced interference between the metasurface and the antenna array. Moreover, the proposed configuration has achieved a wider bandwidth of 5.96 GHz (27.38–33.34 GHz), a maximum gain of around 12.7 dBi, and a radiation efficiency of 94% despite its 20.5×20.6×0.508mm3 miniaturized size. The design is validated by testing the fabricated prototypes. Compared to state-of-the-art literature, the proposed design renders itself a feasible solution for millimeter wave communication devices and systems owing to its smaller physical footprint, broader bandwidth, higher gain, and improved radiation efficiency.