BROADBAND FOUR-BEAM MIRROR ANTENNA (OPTIONS) Russian patent published in 1997 - IPC

FIELD: direction finding and tracking systems. SUBSTANCE: mirror antenna has reflector in the form of cutout from paraboloid of revolution and multielement feed in the form of four-element hexagonal grid of open ends of H- wave guides. H-wave guide ridges extend beyond plane of their aperture in the form of projections with distance between them gradually increasing to 0.25-0.45 λ_H. Feed is placed in spherical absorbing screen of diameter not less than λ_H so that plane of open ends of H-wave guides protrudes above external surface of screen by maximum λ_H. Antenna feed may be optionally placed coaxially in absorbing screen shaped as truncated cone so that angle between longitudinal axis of feed and direction to screen edge from center of feed aperture is 0-15 deg. larger than angle between longitudinal axis of this feed and direction to reflector edge from center of feed. EFFECT: reduced variation in level of directivity pattern intersection in equisignal direction within wide frequency range. 2 cl, 7 dwg