Patent ID: 6337643
Filing Date: 2002-01-08
Classification: G06F,H03M

Abstract:
Process for the generation of a random signal, comprising:a first noise generation step; a second noise filtering step to obtain a signal x(t) with a predetermined spectral envelope H(f); a third step in which a non-linear function g is applied to the signal x(t) in order to give a signal y(t) similar to a predetermined amplitudes histogram f(y), the function g being defined by the following relation: y=g&af;(x)=Î±&it;&Integral;0x&it;P&af;(u)f&af;(u)&it;&dd;uwhere the function P is the histogram of the signal x(t) to which the third step is applied and &agr; is an amplitude adjustment factor that depends on the required amplitude for the signal y(t); a fourth step in which a pulse response filter w(t) is applied to the signal y(t) to correct its spectral envelope and obtain an output signal s(t) with a predetermined spectral envelope H(f), the pulse response w(t) being an inverse Fourier transform of a frequency function W obtained by dividing the function H(f) by the modulus Y2(f) of the Fourier transform of the signal y(t), and then multiplying by a constant &bgr;.