A Family of Designs for Rapid Scanning Radar Antennas

A family of parallel-plate radar lenses is derived from an optical result of Luneberg. These lenses theoretically produce a beam with a straight wave front from a point source of microwave energy located at any point on a certain circle. A constant refractive index greater than one in the planar portion of the lens permits an inversely proportional smaller feed-circle radius. This provides the possibility of reducing feed-circle size to a point where rapid rotation of the source is feasible, producing rapid scan by the output beam.