| 摘要 |
1,074,113. Aerials. COMPAGNIE GENERALE DE TELEGRAPHIE SANS FIL. Aug. 4, 1964 [Aug. 6, 1963], No. 31102/64. Heading H4A. In a radar aerial system in which vertical scanning of one or more radio beams is effected by electrical means; a number of waveguides 1, 2 ... n, Fig. 3, are disposed parallel and side by side, with their upper faces, which have radiating slots, substantially co-planar, and the assembly is fed with energy from one end, means being provided for controlling the relative phase of the input to each waveguide. As described, the waveguides are fed by a horn C via a lens L, controllable ferrite phase shifters D inserted in their input ends producing equal phase difference # between adjacent waveguides, so that if the phase at waveguide 1 is taken as zero (datum) the phase at waveguide 2 is # and at waveguide n, (n - 1)#. When the waveguides are lying in a horizontal YOX plane, Fig. 4 (not shown), and are pointing in the direction. of OX, the radio beam will be at an angle 6 to the vertical OZ, and this angle may be varied for vertical scanning by ganged control of the phase shifters. In another embodiment, Fig; 5 (not shown), three feed horns (F 1 ,F 2 , F 3 ) are provided which when simultaneously excited give rise to a series of beams at different angles of elevation in the ZOY plane. In yet another embodiment, Fig. 7 (not shown), the lens (L) is dispensed with, a sectoral horn (S) being fed by four horns (F o , F 1 , F 2 , F 3 ) and additional ferrite phase shifters (E) are provided in some of the waveguides. In a practical application, Fig. 8, a sectoral horn S is folded beneath the waveguide assembly G, the complete unit being mounted on rollers R in a pit, with an associated transmitter-receiver in a cellar below. The surface of the waveguide is protected by blocks of layered plastic material and the aerial structure is carried on bricks in order to reduce the effect of blast, it being stated that a pressure shock wave of 20 lbs/sq. in. can be withstood without causing more than a temporary interruption of service. |
