NON-DIRECTIONAL MICROWAVE ANTENNA Russian patent published in 1999 - IPC

FIELD: microwave antenna equipment. SUBSTANCE: device has four bent dipoles which are located in orthogonal planes over metal screen. Goal of invention is achieved by design of dipoles as quarter circles with linear piece which is directed in radial. Linear pieces are located close to antenna center and are short-circuited to screen. Ends of dipoles which are located further from center, are driven with equal amplitude and progressive quarter phase shift. Dipole length is 3/4 of average wavelength. Length of linear pieces is not less than quarter of average wavelength. EFFECT: beam pattern is near-isotropic in upper half- space.