Stochastic resonance in a mono-stable system subject to frequency mixing periodic force and noise

The phenomenon of stochastic resonance (SR) in a biased mono-stable system driven by in multiplicative and additive white noise and two periodic fields is investigated. Analytic expressions of the signal-to-noise ratio (SNR) for fundamental harmonics and higher harmonics arc derived by using the two-state theory. It is shown that the SNR is it non-autonomic function of the intensities of the multiplicative and additive noises. its well as the bills of the mono-stable system and SR appears at both fundamental harmonics and higher harmonics. Moreover, the higher the order of mixed harmonics is, the smaller the SNR values ire, that is, the suppression exists Cor higher harmonics. (C) 2007 Elsevier Ltd. All rights reserved.