Stochastic resonance in the Heaviside nonlinearity with white noise and arbitrary periodic signal

A Heaviside nonlinearity with adjustable threshold is fed by an arbitrarily distributed white noise plus a periodic signal of arbitrary wave form. A general and exact treatment demonstrates that this system is capable of stochastic resonance in a large variety of conditions and offers a complete characterization of this property. In particular it gives the possibility of observing nonzero phase shifts with nondynamic stochastic resonance.