| 摘要 |
<p>The deflector for electromagnetic waves in the VHF/UHF ranges is located between transmitter and receiver to direct the path of the waves when there is insufficient direct line of sign between transmitter and receiver. The deflector consists of a reflecting surface so shaped and positioned that a divergent beam received from the transmitter, with a wide wavefront, is converted to a parallel beam directed towards the receiver. Beaming may be effected in both horizontal and vertical planeS. The deflector may be formed of a pair of elements, the first having the shape of a concave parabolic reflector and the second, a concave or convex reflector re-radiating the energy received from the first, to form the parallel onwards beam.</p> |
