A signal processor utilizes a globally nonlinearly coupled array of nonlinear dynamic elements. In one embodiment of the invention, these elements take the form of bistable overdamped oscillators. The processor exploits the phenomenon of stochastic resonance to amplify a weak periodic signal embedded in noise. In this signal processor, a system or plurality of nonlinearly coupled overdamped oscillators is subject to a weak periodic signal embedded in a noise background. For communication or detection applications, this weak signal component is the signal of interest. A reference oscillator is chosen from the plurality of overdamped oscillators, and is given a time scale for relaxation that is longer than the remaining oscillators. The output of the reference oscillator is analyzed for signal processing purposes in response to the signal and noise. A detailed numerical analysis of the full dynamics of the bistable element represented by the reference oscillator has shown that the signal-to-noise ratio (SNR) of the entire processor system reaches a maximum at a critical noise variance value. By using a number of overdamped oscillators working together, an enhancement of SNR can be achieved over that of the use of a single oscillator.