| 摘要 |
<p>A circular waveguide dual antenna feed for TVRO reception, which transfers horizontally and vertically polarized received signals in the circular waveguide simultaneously into two coaxial lines parallel with and offset from the circular waveguide axis. For coupling to existing LNA's, the separate coaxial lines from the circular waveguide are extended into a rectangular waveguide which couples to the input - mixer of the conventional LNA. Alternatively, the separate coaxial lines can be coupled separately to two LNA's or they can be combined into a single output terminal. Switching means are provided in each channel so that each channel can be rendered operative or inoperative, as desired. Diode switches are shown. The device requires no moving parts.</p> |
