Design and testing of a lightweight, planar microwave lens

The authors outline the design, fabrication, and testing of a planar microwave lens. The lens consists of two planar arrays of lightweight printed circuit antennas interconnected by microstrip lines whose length varies as a function of position on the lens. Microwave energy is coupled from one face of the lens to the other by means of a slot etched in the ground plane. At 8.0 GHz the lens is ten wavelengths across, is less than 1/8 in thick, and weighs less than 4 lbs. The lens can scan a beam over a +or-30 degrees region in both the azimuth and elevation planes. The overall lens efficiency is 50%, a 25% increase over previous lens designs.<<ETX>>