| 摘要 |
PROBLEM TO BE SOLVED: To obtain a reflected power monitor circuit, which can precisely monitor a reflected power, irrespective of the phase of the reflected power. SOLUTION: An attenuator 21 is connected to a coupling terminal 14 of a directional coupler 11. A phase device 22, having one terminal short-circuited or opened, is connected to the attenuator 21. While a power (Pic2) is made equal in amplitude and opposite in phase to those of a power (Piso), the attenuator 21 and the phase device 22 are adjusted to cancel the powers. According to this reflected power monitor circuit, a monitor power will not change, even if the reflecting power changes the phase, so that a power monitor circuit 16 can correctly monitor the reflected power. |
