| 摘要 |
PROBLEM TO BE SOLVED: To increase antenna efficiency by displacing a primary radiator. SOLUTION: In an offset parabolic reflector which contains an offset parabolic reflector 2 and a primary radiator 4, the radiator is arranged so as to be located on the side of a tip direction of the reflector 2 from the focal position F of the reflector 2, Thus, the effective opening area of an antenna is expanded and antenna efficiency that accompanies the expansion increased. On the other hand, the antenna efficiency is reduced based on a phase error. The beam deflection angleθF in the reflector 2 is selected at the angle where the efficiency connecting the efficiency increase based on the increase of the effective opening area of the reflector 2 and the efficiency drop based on the phase error of the displacement of the radiator 4 is larger than the efficiency where the radiator 4 is located at the position F.
|
