Approximated synthesis design of plano-convex teflon lens suitable for microwave traffic monitoring sensor

The plano-convex lens antenna fed by a single patch is studied for microwave traffic monitoring sensor with considerations of small size and low cost. In this paper, the AUT is measured experimentally under practical situations considering focal plane shift and metallic shielding effects for the commercial packaging of a sensor. An approximated simple formulation for extracting the parameters of a plano-convex lens, based on geometrical optics, is also deduced using Fermat´s principle of equi-phased ray condition. The fabricated plano-convex lens shows HPBW of below 7.5 degree, side-lobe level below -29 dB with specific aperture distribution of a parabolic-squared taper on a pedestal