Patent ID: 8355467
Filing Date: 2013-01-15
Classification: G01R

Abstract:
1. An amplitude probability distribution measurement apparatus comprising: a frequency analysis unit having Analog/Digital (A/D) conversion means for sampling an input signal, converting the input signal into digital data, and outputting the digital data and frequency selection means for extracting predetermined frequency band components to be measured from the digital data; a level detection unit for detecting an amplitude of each of the frequency band components to be measured which are acquired by the frequency analysis unit; and an amplitude probability distribution measurement unit for finding an amplitude probability distribution, which is a probability that an amplitude of each measurement frequency band component to be measured exceeds a predetermined threshold value, every lapse of time, wherein said frequency selection means comprises Fast Fourier Transform (FFT) type processing means forming a filter for extracting said frequency band components to be measured from the digital data through an FFT operation, filter bank type processing means which is composed of a plurality of filters for extracting said frequency band components from the digital data, and a selector for switching an output extracted from said FFT type processing means and an output extracted from said filter bank type processing means according to said frequency band components to be measured, the amplitude probability distribution measurement apparatus further comprising correction means for comparing amplitudes of the frequency band components to be measured, extracted by the FFT type processing means, and amplitudes of the frequency band components to be measured, extracted by the filter bank type processing means, and for correcting the amplitudes outputted by the FFT type processing means and generated when the FFT operation is performed based on a result of the comparison.