GAIN MONITOR DEVICE

摘要

PROBLEM TO BE SOLVED: To accurately monitor a gain of a high frequency amplifier in accordance with a decibel value.

SOLUTION: A gain monitor device which monitors a gain of a high frequency amplifier based on a first high frequency signal of an input side signal path of the high frequency amplifier and a second high frequency signal of an output side signal path of the high frequency amplifier comprises: a decibel value variable attenuator which varies an attenuation amount of the first high frequency signal with a decibel value; a first detector which detects the high frequency signal outputted from the decibel value variable attenuator; a second detector which detects the second high frequency signal; a voltage comparator which compares a first detection voltage outputted from the first detector with a second detection voltage outputted from the second detector; a control means which controls the attenuation amount of the decibel value variable attenuator on the basis of a comparison result of the voltage comparator; and a determination means which determines the gain of the high frequency amplifier in accordance with the attenuation amount of the decibel value variable attenuator controlled by the control means.

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