Geodesic Lens Antennas for 5G and Beyond

TLDR

Geodesic lenses offer new opportunities for high‑performance 5G/6G antennas. Geodesic lenses operate by guiding rays along the shortest optical paths on a curved surface, can be realized as fully metallic graded‑index structures, and when paired with a feeding network and radiating transition can generate multi‑beam antennas for one‑dimensional coverage diversity. Prototype tests in the Ka‑band show that geodesic‑lens antennas deliver high directivity, efficiency, and multi‑beam spatial diversity, making them a cost‑effective solution for 5G/6G.

Abstract

This article summarizes the recently discovered opportunities of geodesic lenses for producing high-performing antennas for 5G/6G communications. First, we explain the operation of these lenses based on Geometrical Optics with rays that follow 'the shortest optical path' on the geodesic surface. Also, we explain the connection between geodesic lenses and rotationally symmetric graded-index lenses. Generally, geodesic lenses can be implemented without the need of dielectric materials, resulting in very efficient devices constructed with a fully-metallic configuration. When combined with a feeding network and a radiating transition, such as a flare or a leaky wave, they can produce a multiple-beam lens antenna, of interest for applications requiring one-dimensional (e.g., azimuthal) coverage diversity such as in cell tower communication systems. Prototypes of these antennas have been recently tested, demonstrating remarkable performance in the Ka-band, part of which is considered for 5G. At high operational frequencies allocated for 5G/6G, geodesic lenses offer an opportunity to produce cost-effective antenna solutions with high directivity, high efficiency and spatial diversity through multiple beams.