Metasurface-Assisted Antenna for Bandwidth and Gain Boost in Extended UWB Applications

Abstract

Unlike traditional narrowband communication antennas that operate within specific frequency bands, UWB antennas utilize frequencies across a wide range, typically spanning from 3.1 GHz to 10.6 GHz. However, most of the existing antennas are characterized by low gain, and there is a growing need to extend the existing UWB frequency range. To achieve this, suitable antennas are required, especially those with high gain and extended bandwidth. On this note, a compact coplanar waveguide (CPW)-fed ultra-wideband (UWB) elliptical patch antenna supported by a reflectarray metasurface (MS) for gain augmentation is reported in this article. The antenna and MS have planar dimensions of 40 mm x 40 mm and 60 mm x 60 mm respectively. The CPW ground features a semi U-shaped slot and a 12-gon elliptical slot for enhanced surface current distribution and bandwidth, respectively. Besides, a simple equivalent circuit representation for the UC is proposed. Our design attains a peak gain of 10.8 dBi, a total efficiency above 90%, and a 149% -10 dB fractional bandwidth (FBW) (2.6-17.75 GHz). The proposed structure is ideal for UWB energy harvesting, sensing, and communication within the C-band (4–8 GHz), X-band (8–12 GHz), and Ku-band (12–18 GHz) due to its large FBW, high total efficiency. and quasi-end-fire radiation performance.