Planar Tapered Metasurface Unit Cell Shaped Array for Augmenting Multipart Radiating Systems for 5G mm-Wave Beam Forming Applications

This article presents a four-port antenna design for beam forming applications between 26GHz to 29GHz, FR2 band of frequencies. It incorporates a gradually tapered size of metasurface unit cell as an array that results in a Gradient Refractive Index Metasurface (GRIM). The metasurface unit cells are meticulously designed to operate at the desired range of frequencies and two such surfaces are integrated with four CPW-fed planar Yagi-Uda antennas, which inherently offer high gain, narrow beam radiation patterns suitable for beam steering purposes. The article presents the design methodologies followed by simulation results for validation. Single and dual antenna beams are generated using the proposed architecture with control over their tilting angles and beamwidth, with stable pattern characteristics over the frequency range of operation. For generating the non-trivial radiation patterns and controlling the same, suitable port excitations are chosen for this multiport antenna system and fixed phase differences are introduced between the ports concerned to enhance the functional diversity of the structure.