Dual reflector antenna with narrow broadside beam for omnidirectional coverage

A new type of high gain omnidirectional antenna is presented, particularly suited for higher frequencies (e.g. milllimetre waves): it is obtained with an axially symmetric dual reflector system, fed with an unconventional feed with conical pattern. The feed radiated field, after reflection on the parabolic subreflector and on the conical main reflector, is uniformly scattered in the plane perpendicular to the axis of the system, with vertical polarisation and narrow vertical beamwidth.