Abstract: A log-periodic slot antenna has adjacent radiating elements connected by off-center co-planar lines thereby providing the required phase reversal and modifying the element impedance to match that of the co-planar line. By providing a ground plane restricted in size to that of the element array a difference pattern can be formed by the single antenna giving a sharp null in the longitudinal direction of the antenna. A dual log-periodic antenna formed from two such single antennas can be fed in-phase and produce two difference patterns one in the co-planar plane and one in the cross-polar plane.

Abstract: A radome-lens comprises a shell of dielectric material having an outer surface in the form of a small circle defined by a sphere and a plane intersecting the sphere, an opening at one end of the shell for reception of an antenna therein, the surface having a central axis which is normal to the plane and extends through the center of the sphere, and an inner surface having a spherical portion centered at a second center disposed along the axis adjacent the first mentioned center but spaced toward the outer surface. When so constructed, the invention functions as a radome in the sense that it houses and protects an antenna in the usual manner and also functions as a lens in the sense that it amplifies the scan angle of the antenna from an angle of less than 90.degree. to 90.degree. or more.