| 摘要 |
PURPOSE:To obtain a shaped-beam antenna containing a primary radiator having a large degree of freedom with a simple constitution by consituting a main reflector with the envelope surface of a line group formed in accordance with the section form of a shaped beam to be synthesized. CONSTITUTION:A main reflector is formed by a part of five types of parabolas 3-7. These parabolas use the phase center point P of a primary radiator 13 as a common focal point and axes Z3-Z7 having different directions with angles theta3-theta7 on the basis of a reference axis Z of the reflector 2. With an antenna of such a consitution, the radio waves of a spherical wave source radiated within a cut plane from the radiator 13 are reflected by parabolas 3-7 and then radiated within the same plane as the radio waves traveling toward each axis. The radiation characteristics within the cut plane are shown by a solid line 40 as mainly a synthetic wave. Thus it is possible to synthesize the desirable radiation characteristics by adjusting the number of parabolas forming cut lines, the size of each parabola, the focal distance and the axis direction respectively. |
