Study on non-linear filter characteristic and engineering application of cascaded bistable stochastic resonance system

This paper addresses the problem of cascaded bistable stochastic resonance system (CBSRS) with large parameters, and reveals its non-linear low-pass filter characteristic. The study results show that weak characteristic frequency component located in low-frequency area can be extracted gradually from strong noise background owing to the energy transfer mechanism from high-frequency area to low-frequency area, as a result, a novel low-pass filter can be achieved ultimately. Compared with conventional digital filter, low-pass filter based-on CBSRS has the advantage of extracting some certain weak low-frequency characteristic components while implementing low-pass filter. Simulated experiments and mechanical fault diagnosis examples are presented in order to demonstrate that CBSRS is a powerful tool for signal processing.