System size stochastic resonance in driven finite arrays of coupled bistable elements

The global response to weak time periodic forces of an array of noisy, coupled nonlinear systems might show a nonmonotonic dependence on the number of units in the array. This effect has been termed system size stochastic resonance. In this paper, we analyze the nonmonotonic dependence on the system size of the signal-to-noise ratio of a collective variable characterizing a finite array of one-dimensional globally coupled bistable elements. By contrast with the conventional nonmonotonic dependence with the strength of the noise (stochastic resonance), system size stochastic resonance is found to be restricted to some regions in parameter space.