基本信息
摘要：1,005,343. Wave guide switches. ALBISWERK ZURICH A.G. Feb. 15, 1963 [Feb. 16, 1962], No. 6153/63. Heading H1W. [Also in Division H4] A single antenna is coupled to both a transmitter and a receiver via impedance transforming networks which contain semi-conductor diodes acting to give the desired high or low impedance. In Fig. 1 the lines A, S, E lead to the antenna, transmitter and receiver respectively. The impedance transforming network across the transmitter comprises lines 9, 10, which are of a length (2n+ 1)#/4 equal to an odd number of quarter wavelengths of the transmitting frequency connected at their ends by diodes 11, 12 inanti-parallel. The line 8 between this network and line A is also of length (2n+ 1)#/4, similarly the network leading to the receiver comprises lines 2, 3 of length (2n+ 1)#/4 and diodes 5, 6. When the trans- mitter S produces an R.F. pulse the diodes 5, 6, 11, 12 conduct in the appropriate half cycles presenting low resistance at the ends of the lines. This means that the input impedance of the branches are high and little energy is lost. On receipt of a pulse by the antenna the diodes are non-conductive because the lower energy of the received pulse is below their threshold voltage. The diodes therefore present high resistance at the end of the lines. The input impedance for lines 2, 3 is low while that for lines 8, 9, 10 is high and so the received energy passes to the receiver. Single diodes in each branch may be adequate in some cases. In order to receive higher signal energies the diodes may be back biased during reception and forward biased during transmission. An alternative embodiment is shown in Figs. 2A and 2B in which oscillatory circuits with zero impedance at the transmitter frequency are used. In the receiver line coupling (2A) the diodes 21 are so connected that they short circuit the input of the receiver for transmitted signals but open the input for reception. In the transmitter line coupling (2B), however, the diodes 25 and 28 provide a signal path during transmission but break the path during reception.
摘要附图：
