| 摘要 |
PURPOSE:To enable the common use of transmitting and receiving antennae to a wide frequency band, by changing over transmission and reception by controlling the high-speed switching of an electronic switch by combining delay wires. CONSTITUTION:The pulse signal from a pulse generator passing through the signal-dividing device 31 of a duplexer 3 is applied not only to a delay wire 33 preventing the cutting off a first part but also to a trigger circuit 36. Trans mitting and receiving electronic switch elements 32, 35 are controlled through a gate generation circuit 37 responding to the output of the circuit 36 and, during a transmission period when there is the output of the delay wire 33, the element 32 is turned ON while the element 35 is turned OFF and a pulse signal is transmitted through a delay wire 34 and the input to a receiving circuit through the element 35 is cut off. In the same way, a receiving pulse signal is inputted to the receiving circuit through the element 35 during a receiving period and the input to the delay wire 3 through the element 32 is cut off. By the changing-over of transmission and reception through this high-speed certain electronic switch, the common use of transmitting and receiving antennae is enabled to a wide high-frequency band. |
