Patent ID: 8886486

Claim:
A device for testing an operating state of an APD (Amplitude Probability Distribution) measuring device that analyzes a frequency band component included in a signal to be measured, detects the amplitude of the analyzed frequency band component, and calculates an amplitude probability, which is the probability of the detected amplitude of the frequency band component exceeding a predetermined threshold value for a unit time, whenever the unit time has elapsed, comprising: a test signal generator that generates a test signal corresponding to the vicinity of a center frequency of the signal to be measured; a control unit that variably controls the amplitude of the test signal in a predetermined level range at random; and a determining unit that determines whether the APD measuring device is operating normally on the basis of the test signal as input to the APD measuring device, a time capture rate indicating that a predetermined amplitude for the unit time and a PDF (Probability Density Function) histogram indicating the distribution of the amplitude is obtained from the APD measuring device.