Output power control device

An output power control device comprising:

• an attenuator to attenuate and output power of a high-frequency signal having a pulse waveform output from an oscillator;
• a high-frequency power amplifier to amplify and output the power of the high-frequency signal output from the attenuator;
• a monitor circuit to monitor the power of the high-frequency signal output from the high-frequency power amplifier, and output a monitor signal according to magnitude of the power of the high-frequency signal;
• and
• a controller to control an attenuation amount of the attenuator based on the monitor signal output from the monitor circuit or based on attenuation amount setting data from a data unit, wherein
• the oscillator generates the high-frequency signal having the pulse waveform in synchronization with a trigger signal,
• the controller starts control of the attenuation amount of the attenuator using an attenuation amount control signal generated based on the attenuation amount setting data, in synchronization with the trigger signal, and
• after receiving the monitor signal, the controller controls the attenuation amount of the attenuator using the attenuation amount control signal generated based on the monitor signal.