The approach for generating a broad-band colored noise is proposed, which a
llows the transition between "red" and "green" noise. The rectification of
the noise with different colors characterized by the net current of a Brown
ian particle moving in a ratchet-like potential is studied by using the dig
ital simulation. The present noise is also compared with the harmonic noise
. The results show that the average current reverses sign when the external
noise is filtered off in the region of low frequencies to a sufficient ext
ent. Finally, a parameter plane of the noise with the numerically estimated
line of the current reversal is plotted. (C) 1999 Elsevier Science B.V. Al
l rights reserved.