A Wide and Tri-band Flexible Antennas with Independently Controllable Notch Bands for Sub-6-GHz Communication System

Abstract

A wide-band and tri-band flexible antenna for fifth-generation (5G) sub-6-GHz communication systems is investigated in this paper. The proposed wideband antenna covers the 5G new radio (NR) mid-band, ranging from 2.8 to 5.35 GHz, while the tri-band antenna is resonating at three different allocated frequency bands (2.45 GHz, 3.5 GHz, and 4.7 GHz) for 5G sub-6-GHz communications. This functionality is achieved by introducing hexagonal split-ring resonators in the radiating element, which can be controlled independently without affecting antenna performance to avoid problems of interference in this frequency spectrum. In addition, the antenna also presents a good conformability characteristic, and the simulated results are confirmed with the measurements of the fabricated prototype.