An antenna comprises: a main reflector being a body of revolution of parabolic shape; a sub-reflector being a body of the revolution of elliptic shape having a circle and a vertex oriented to the main reflector and being placed between the circle and the main reflector, one focal point of the sub-reflector being placed on the axis of revolution and the other focal point of the sub-reflector being placed out of the axis, the sub-reflector circle being placed in the plane of the main reflector edge circle; a radiator being placed along the axis of revolution of the main reflector and being placed between the main reflector and the sub-reflector; and wherein the sub-reflector has eccentricity ranging from 0.55 to 0.75.