Analysis and Synthesis of a Bipolar-based Circuit with Stochastic Resonance

Stochastic resonance is a nonlinear effect which allows the improvement of the detectability of a signal in noise through noise addition. This can be achieved under bi-stability conditions provided a suitable design is carried out. Here, a first practical implementation at RF frequencies is presented, using two bipolar transistors in cross-coupled configuration. The circuit nonlinear behavior has been analyzed using specific techniques to obtain the coexisting solutions. Applying bifurcation control, the circuit response is preset to improve the signal detectability for given input power. The stochastic resonance has been experimentally confirmed with promising results.