Radio wave emitting device

A radio wave emitting device comprising:

• a cavity configured to accommodate an irradiation target;
• one or more signal generators configured to generate one or more high frequency signals;
• a signal amplifier configured to amplify the one or more high frequency signals and output a plurality of amplified high frequency signals;
• a plurality of radio wave emitters configured to emit a plurality of radio waves into the cavity based on the plurality of amplified high frequency signals;
• a plurality of measurers configured to output one or both of (i) temperature measurement values and (ii) reflected-wave electric power measurement values, the temperature measurement values each indicating a temperature of a corresponding one of the plurality of signal amplifiers, and the reflected-wave electric power measurement values each indicating an electric power of a reflected wave flowing back through a corresponding one of the plurality of radio wave emitters;
• and
• a controller configured to control the one or more signal generators and the plurality of signal amplifiers;
• wherein:
• the controller is configured to switch an operation of the radio wave emitting device from a normal operation to a protection operation when the controller determines, during execution of the normal operation, that protection is necessary for at least one of the plurality of signal amplifiers, based on one or both of the temperature measurement values and the reflected-wave power measurement values;
• the normal operation includes setting electric power target values for the plurality of radio waves to respective normal target values for the plurality of radio wave emitters;
• the protection operation includes setting the electric power target values for the plurality of radio waves to respective protection target values for the plurality of radio wave emitters;
• for one or both of a protection target radio wave emitter corresponding to a signal amplifier for which protection is necessary and a radio wave emitter of the plurality of radio wave emitters other than the protection target radio wave emitter, a protection target value is lower than a normal target value;
• and
• the protection target values for the plurality of radio wave emitters are set in such a manner that a power consumption distribution in the cavity when executing the protection operation is closer to that when executing the normal operation than that when only the electric power target value of the protection target radio wave emitter is set to the protection target value.