we investigate a technology for reconstructing nanosecond pulse noise hidden signals via stochastic resonance, which is based on optical bistability in the fabry-perot (f-p) cavity with graphene. the bistable properties are analyzed with different initial wavelengths and fermi energies. the system is tunable and the bistable behavior of the output intensity can be accurately controlled to obtain a cross-correlation gain larger than 10 in a wide range of input signal-to-noise (snr) ratio from 1:8 to 1:45. meanwhile, the distortion of the output signal and the pulse tailing caused by the phase delay can be reduced to a negligible level. this work provides a potential method for detecting low-level or hidden pulse signals in various communication fields.