Patent ID: 6300915
Filing Date: 2001-10-09
Classification: H01Q

Abstract:
A vertical array antenna, including a plurality of four-dipole sub-arrays, comprising:a support mast aligned vertically;lower, middle and upper sub-arrays, each including four dipoles extending from the mast at 90 degree azimuth separations, each dipole comprising:(a) left and right conductive L-shaped strips having (i) respective left and right parallel portions extending outward from the mast in parallel spaced adjacent relation and (ii) left and right arm portions extending laterally from the respective parallel portions, oppositely from each other and diagonally to horizontal, and(b) a conductive frontal strip extending in parallel spaced adjacent relation to a portion of the combined length of said left and right arm portions to form a frontal divided transmission line structure; andan excitation arrangement coupled to intermediate points along the parallel portions of the L-shaped strips of each dipole to provide omnidirective phase-progressive excitation of each sub-array, with (i) said middle sub-array having phase-progressive excitation of reference amplitude and phase, (ii) said lower sub-array having phase-progressive excitation of nominally 70 percent amplitude and plus 90 degrees phase rotation relative to said reference amplitude and phase, and (iii) said upper sub-array having phase-progressive excitation of nominally 70 percent amplitude and minus 90 degree phase rotation relative to said reference amplitude and phase.