| 摘要 |
An antenna array is fabricated from an upper plate 1 consisting of an array of stepped horn elements 3 and a lower plate 2 comprising a waveguide structure 5. The two plates are attached tog et her by means of heat welding or solvent welding. In the case of heat welding the lower plate 2 is provided with a pattern of ribs (11, Figs 6 and troughs and grooves, the material of the ribs being caused to 7) and the upper plate 1 is provided with corresponding flow into the troughs following application of heat to the interface to the two plates, thus causing the two plates to become attached. In the case of solvent welding, the rib and trough formations are omitted. The mating surfaces of the plates are brushed with dichloromethane and brought into abutment, causing the plates to become attached together. Subsequent to attachment, the structure is immersed in an electroless copper plating bath so that a thin film of copper is deposited on the exposed surfaces of the structure. Thus any imperfections in the flatness of the mating surfaces which would otherwise cause undesirable leakage of microwave radiation are effectively compensated for by the copper film. Alternatively silver or aluminium may be used to plate the structure. <IMAGE> |
