ELLIPTICALLY POLARISED ANTENNA Russian patent published in 2015 - IPC H01Q9/00 

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to antennae for spacecraft operating at orbits at an altitude of 400 km to 1000 km. The beam pattern of such antennae must have a maximum in the directions ±(60°-70°) and an elliptic coefficient of not less than 0.4 in an angle sector of -70° to 70° from the antenna axis. The spacecraft antenna comprises a reflector, an auxiliary mirror and a coaxially arranged radiator in the form of an open end of a circular waveguide with diameter d_W. The reflector is made from multiple coaxial and adjoining metal surfaces of truncated cones, wherein the larger base of each previous cone is the smaller base of each next cone, and the smaller base of the first cone is formed by the open end of the circular waveguide over which an auxiliary mirror is mounted at a height of h=d_W-2.5d_W, said auxiliary mirror being in the form of a metal disc with diameter d_Z≤1.2d_W. If the reflector is in the form of three coaxial surfaces of truncated cones, the base angle of the first cone is 0°<β<15°, the base angle of the second cone is 20°≤γ≤75° and the base angle of the third cone is 1°≤α≤20°. If β=0°, if the reflector consists of two cones, the base angles of the cones are in the ranges 1°≤α≤5° and 40°≤γ≤50°. Owing to the extended multi-cone form of the surface of the reflector, as well as the arrangement of a flat auxiliary mirror over the reflector, an optimum antenna beam pattern is provided, with the required elliptic coefficient greater than 0.4 and with maximum radiation in the angle sector ±(60°-70°), which enables to use said antenna on spacecraft.

EFFECT: producing an antenna with allows maximum radiation of elliptically polarised electromagnetic waves.

3 cl, 3 dwg