Parabolic antenna for satellite transmitter or receiver - has signal source, in offset base, coupled through two rotatable mirrors to reflector

摘要

The dish aerial for transmission or reception of satellite signals has a principal parabolic reflector (1) supported on a fork structure pivotable about a vertical axis (4) and carrying blocks (8) serving as a horizontal rotational axis (7) for the reflector. A radio-electric source (9) is located in a base structure (5) and electromagnetic radiation from the source is transmitted by a set of mirrors (13,14) through a central opening of the reflector across the pivot. The fork supports the blocks (8) by two di-symmetrical branches (3A,B) (relative to the vertical axis) with one mirror (13) at the intersection of the vertical and horizontal axes being rotatable about the vertical axis with the structure. The other mirror (14) is at the intersection of the horizontal axis and the reflector axis (21) and is rotatable about both the horizontal and vertical axes.