Ultra-wideband Metamaterial-based Rectangular Microstrip Antenna for Sub-6 GHz 5G and other Microwave Applications

This paper presents a novel design of an ultra-wideband metamaterial-based rectangular microstrip antenna for sub-6 GHz 5G and other microwave applications. The proposed antenna consist of a rectangular microstrip patch, two metamaterial unit cells, Flame Resistant (FR-4) substrate and partial ground plane. The metamaterial unit cell comprises complementary split ring resonator (CSRR) with double negative characteristics (negative permeability and negative permittivity) as well as negative refractive index (NRI). The NRI medium enhanced the bandwidth and radiation efficiency of the antenna by reducing the surface waves and mutual coupling. The antenna operates over frequency range of 3.4009 to 11.721 GHz and 2.869 to 3.211 GHz, covering the sub-6 GHz 5G bands and other microwave applications such as Wi-Fi, WiMAX, and WLAN. Also, the proposed antenna had optimized dimensions of and exhibited good impedance matching, omnidirectional radiation pattern, and stable gain across the operating band. From simulation results, a combined bandwidth of 8.66 GHz was achieved which shows good agreement with outlined objective. The proposed antenna is suitable for sub-6 GHz 5G and other microwave applications that require ultra-wideband performance and low-profile design.