PURPOSE: To realize not only the elimination of the undesired radiation wave but a low side lobe of the antenna radiation pattern, by enclosing the periphery of the path of the electric wave excluding the vicinity of the focus of the reflector with the electric wave absorber.
CONSTITUTION: The focus F1 of the secondary reflector 2 in the figure coincides with the phase center of the feeding horn 1. And the electric waves coming from the focus F1 are stopped down as shown in the solid lines at the common focus F2 of the secondary reflector 3 and the main reflector 4. At the vicinity of the focus F2, a hole of a fixed radius is drilled in the direction of the reflector 4 and so as to give no disturbance to the electric waves which form the main beam. And at the same time, the electric absorber 6 encloses the periphery of the path of the electric wave from the focus F1 through the focus F2. As a result, the leak waves coming from the reflectors 2 and 3 plus the undesired radiation wave, i.e. the diffracted wave at the edge of the reflectors 2 and 3 can be eliminated. Thus a low side lobe is possible for the antenna radiation pattern.
KIMURA YASUHIRO
YAMAMAE MIZUHO
ABE KOUJI
FURUNO TAKAYOSHI
MITSUBISHI ELECTRIC CORP