Information transmission and storage sustained by noise

The propagation of a low frequency periodic signal is studied in two different devices: (a) a chain of one-way coupled bistable oscillators subject to uncorrelated additive noise and (b) a chain of the same kind of oscillators shaped in the form of a ring. In both cases the oscillators are assumed to operate in the regime of stochastic resonance. The study is performed through numerical simulations. An emergent property of the system is found: a fault tolerant transmission that enhances reliability at the expense of efficiency. In the case of the ring a delayed coupling between the oscillators is proposed. Only one oscillator of the system, operating in the regime of stochastic resonance, is driven by an external force. This is assumed to act during the time that takes the signal to traverse the whole device. A traveling wave is thus found to be transmitted several times along the ring with a small damping. A characterization of this time as a function of the level of noise and intensity of coupling is shown. We also study the occurrence of a time delay in the transmission of the signal along the line. (C) 2002 Elsevier Science B.V. All rights reserved.