Aerial system for broadcasting having a passive middle antenna flanked by two end-fed antennas

摘要

An antenna system for broadcasting comprises a coplanar array of three vertical aerials spaced a quarter wavelength apart, the middle aerial serving as a passive reflector while the outer two are concurrently energized with currents of equal amplitude and frequency in phase or in phase opposition with each other. The resulting radiation pattern is circular in the first instance; in the second case the pattern is generally hourglass-shaped and bisected by the common plane of the aerials.