Conformal Parallel Plate Waveguide Polarizer Integrated in a Geodesic Lens Antenna

Abstract

Here, we propose a low profile polarizing technique integrated in a parallel plate waveguide configuration, compatible with fully metallic geodesic lens antennas. The geodesic shape of the antenna is chosen to resemble the operation of a Luneburg lens. The lens is fed with 11 waveguide ports with 10°separation producing 11 switchable beams in an angular range of ±50°. Two metallic polarizing screens are loaded into the aperture of the antenna to rotate the electric field from vertical linear polarization, which is the polarization of the TEM (transverse electromagnetic) mode supported in the lens, to +45°linear polarization. Since the polarizing unit cells are integrated into the aperture of the antenna, the final design is compact. Additionally, the size of the polarizing unit cells is about 0.55λ at the central frequency of operation making the antenna suitable to produce an array formed of stacked lenses. A prototype of the antenna in the Ka-band was manufactured and tested, verifying the performance obtained in simulations.

V-Band Monolithic Additive-Manufactured Geodesic Lens Array Antenna

“…Traditionally, the use of subtractive manufacturing (CNC milling) and subsequent assembly of several pieces using screws has been used to produce geodesic lens antennas, including single-lens designs [5], [6], [10], [12], [30] or arrays of lenses [13]. However, this fabrication method has problems when scaling in frequency above the K a -band, for example in V-band.…”

Two-Dimensional Beam Steering Using a Stacked Modulated Geodesic Luneburg Lens Array Antenna for 5G and Beyond

“…The profile is defined by continuously differentiable functions, meaning that the folding is accounted for in the design, thus reducing the phase aberrations compared to [28]. Moreover, in [30], the integration of a polarizer at the flare of a geodesic lens antenna was proposed for dual-polarization applications. While geodesic lens antennas provide relatively simple manufacturing and high efficiency, these PPW lens antennas can only scan in one plane, which is not sufficient in some applications.…”

“…Here, we present a vertically stacked array of four water drop lens antennas. Stacking geodesic lenses was previously proposed in [30], but no demonstration of the scanning capabilities has been reported until now. The lens element is a scaled version of the lens in [18].…”

Geodesic Half-Maxwell Fish-Eye-Lens Antenna

“…They also have potential for space applications, as they provide high-power handling and can work in extreme environments [19]. Examples of geodesic lens antennas that mimic the performance of a Luneburg lens are reported in [20]- [22]. These are particularly attractive because they provide directive beams in different directions with low scan losses.…”