Subreflector for Cassegrain microwave antenna

摘要

The reflector (103) has a first circular ring (104) of cylindrical shape formed of a conductor material and directed toward a principle reflector. The ring has a diameter equal to an outer diameter of the reflector. The ring has one end fixed to outer side of reflector so as to project towards reflective side of the reflector, and is of specific height (H) to reduce the radiation spillover of the reflector. Preferably a second ring (105) in the form of a circular crown is fixed to the free edge of the first ring. The second ring has the same internal diameter as the first, and has a specific height (h) to further reduce reflector spillover. The values of the specific heights (H, h) are preferably of the order one quarter wavelength at the antenna operating frequency.