Millimeter-Wave High Gain Lens Antenna with Reduced Focus Distance

Design of a 57-64 GHz high gain lens antenna with reduced focus distance is presented. The antenna is composed of a thin lens with a waveguide feed element, and trans-and twist-reflectors realized using a PCB technology. The antenna structure forces the radiation emitted by the feed to travel between the reflectors and to radiate from the lens. Such behavior is achieved by polarization-selective properties of the reflectors. As a result, the focus distance of a thin lens is reduced by 3 times with maintaining antenna high electric performance and beam scanning capabilities. Antenna prototype with 120 mm diameter and only 65 mm lateral dimension was designed and experimentally investigated. The antenna has less than -12.4 dB reflection coefficient and more than 33.9 dBi gain in the 57-64 GHz frequency range making the proposed concept perspective for applications in point-to-point radio systems.