CONFORMAL TWO DIMENSIONAL ELECTRONIC SCAN ANTENNA WITH BUTLER MATRIX AND LENS ESA

摘要

An antenna and antenna excitation method. The inventive antenna includes acylindrical array (20) of radiating elements. Each of the elements is mountedat a predetermined substantially transverse angle relative to a longitudinalaxis. A circuit (30) is included for providing an electrical potential betweenat least two of the elements effective to scan a transmit or a receive beam ofelectromagnetic energy along an elevational axis at least substantiallytransverse to the longitudinal axis. In the illustrative embodiment, the arrayincludes a stack of the planar, parallel, conductive, ring-shaped radiatingelements, each of which is filled with ferroelectric bulk material. A secondcircuit (70) is included for exciting at least some of the elements to causethe elements to generate a transmit or a receive beam of electromagneticenergy off-axis relative to the longitudinal axis. In the preferredembodiment, the second circuit is a Butler matrix and is effective to causethe beam to scan in azimuth about the longitudinal axis, the azimuthal axisbeing at least substantially transverse to the longitudinal axis and theelevational axis.