Abstract
The purpose of this paper is to present a new method to measure the amplitude probability density function (P.D.F.) of continuous random signals ro random pulses employing the analog-to-digital converters (A.D.C.): successive approximation type or multidiscriminator type. These type of A.D.C. are fast but with very poor channel width uniformity. The channel width inaccuracy is called differential non-linearity (D.N.L.), and is the most influential characteristic of A.D.C. in the measurement of P.D.F.. We have already established two methods to measure P.D.F. reducing the measurement error of P.D.F. due to D.N.L. (D.N.L. error).
In this paper, a new method to measure P.D.F. avoiding the growth of D.N.L. error using Fast Fourier Transform (F.F.T.) is proposed. In this method, the amplitude is transformed into the frequency of a sinusoidal wave. Then, the frequency corresponding to the maximum auto power spectrum of this sinusoidal wave gives correct amplitude avoiding the influence of D.N.L.. The experimental results are shown to demonstrate the feasibility of this method.
