The stochastic resonance phenomenon in a bistable system under the simultaneous action of multiplicative and additive noise and periodic signal is studied by using the theory of signal-to-noise ( SNR ) ratio in the adiabatic limit. 利用随机共振理论,我们研究了在乘性和加性噪声以及周期性驱动力共同作用下的双稳系统的随机共振现象。