Using AIRP-m metasurface as LWP for bandwidth and gain enhancement in designing compact quasi-TE dipole antenna for Wi-Fi applications

Abstract

In this article, we have proposed a compact quasi-TE dipole antenna loaded with an angle insensitive reflection-phase metasurface (AIRP-m). The antenna consists of folded quasi-dipoles as directors, quasi-TE dipole elements as radiators and a cutaway coaxial balun acting as an integrated feed driven element, thus mimicing a Yagi-uda configuration asserting excellent boresight directive radiations. The AIRP-m shows angle invariance property at resonant frequency, also acts as an effective incident linear wave polarizer (LWP) for bandwidth and gain enhancement. Exploiting such intrinsic electromagnetic properties of metasurface structures, a 4 × 4 array of periodic meta-units as excellent LWP coupled into the quasi-TE dipole antenna for overall performance improvements. This configuration achieves compact design embodiment, wideband mode (3.8–6.95) GHz of 58.60% impedance bandwidth (IBW), high boresight gain (10.3 dBi), radiation efficiency (>70%) and −20 dB far-field back lobe suppression. A prototype antenna of size 0.85 λ0×0.85λ0×0.084λ0 (λ0 = lowest operating wavelength at 3.8 GHz) has been fabricated, where both simulated and experimental results shows good agreements, to be explored in Wi-Fi systems.