| 摘要 |
630,897. Radio receiving apparatus; directive radio systems. GENERAL ELECTRIC CO., Ltd., and ESPLEY, D. C. Jan. 24, 1947, No. 2272. [Classes 40 (v) and 40 (vii)] To cancel the effect of unwanted coupling between the transmitting and receiving portions of a combined transmitter-receiver equipment a passive reflector is provided reflecting energy from the transmitting aerial to the receiving aerial in such phase and amplitude as to cancel the effect of the coupling. In a two-way repeater station as shown, unwanted coupling between transmitting aerial A1<1> and receiving aerial A2 is counterbalanced by means of a reflector B directing an equal and oppositely phased signal from All to A2. Reflector C similarly balances the unwanted coupling between A2<1> and A1. The reflectors B and C may be of sheet metal and adjustable as to their distance from the aerials. The amplitude of the reflected energy may be altered by changing the size of the reflectors or, preferably, by rotating them so that their inclinations to the energy paths and thus their effective area is varied. The whole antenna system including the reflectors may conveniently be supported on a common structure. |
