| 摘要 |
A compact, mechanically-steered antenna especially applicable for mobile terminals for receiving signals broadcast by satellites, is adjustable in azimuth and elevation. The antenna's active element can be rotated in azimuth through 360 degrees. Rotary couplings in the signal path are avoided by means of a flexible coupling. The flexible coupling conveniently comprises a torsion spring and the feedline, typically a highly-flexible coaxial cable, passes through it. The active element is mounted upon a first support member and rotatable relative to it about the boresight of the antenna. A second support member is mounted upon a base member and rotatable relative to it in azimuth. The first support is mounted upon the second support by means of a hinge coupling which permits pivoting of one support member relative to the other to adjust the elevation angle. Pivoting of the support members relative to each other is effected by longitudinal displacement of the flexible coupling which is fixed at one end to the antenna element and extends slidably through the second support member. A drive motor rotates the second support member and a linear actuator displaces the flexible coupling. Sensors detect the azimuthal angle.
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