| 摘要 |
PURPOSE:To obtain sectoral beam having flat tip of main beam directivity and steep rise of beam by placing a primary horn at the shortest focus position of a reflecting mirror formed by pressing and deforming a centered parabolic reflecting mirror. CONSTITUTION:When uniform pressure directed from one end and another end of the X-axis to the focus F0 is applied to an open periphery of an original centered parabolic reflecting mirror 1, a deformed reflecting mirror 4 is formed as the reflecting mirror 1 is regarded as a flat spherical shell and the periphery is not perfectly free. Intersecting line of a fixed plane and Z of this reflecting mirror forms an ellipse with major axis A'B'. By placing a primary horn, not shown in the figure, that has proper illumination distribution at F2 point which is positioned at the shortest focal length, above-mentioned reflecting mirror works as a sectoral beam antenna. The tip of main beam directivity of this sectoral beam antenna is flat and sectoral beam having steep rise of beam can be obtained. Further, it has excellent F/B characteristics. |
