| 摘要 |
PURPOSE:To protect a transmitter securely by preventing malfunction due to an electromagnetic interference wave and by detecting reflected power accurately, by adding a simple circuit. CONSTITUTION:A delay line 13, a gate 15 and a gate signal generator 17 are added. A trigger signal from a trigger generator 1 is divided into two by a trigger controller 2: one is sent to a pulse modulator 3, and the other to the generator 17, respectively. Then, the gate 15 is closed only during the period of the pulse width of the generated gate signal, and the malfunction of a comparator 7 due to an electromagnetic interference wave is prevented. The reflected power extracted by a directional coupler 15, on the other hand, is detected by a detector and amplifier 6 through the delay line 13 and its output is sent to the gate 15. At this time, the gate 15 is open, so the reflected power detection signal is sent to the comparator without being interfered. Thus, a transmitter is protected securely. |
