Abstract: A new stochastic resonance algorithm for detection of weak chemical signal was proposed. The algorithm was achieved through periodic modulation to realize the system resonance. After a detailed discussion of the parameters in the system, a simulated signal and experimental noisy signals of a set of CCl₄ sample were analyzed by the method. It was proven that the proposed algorithm is very efficient in improving the signal to noise ratio of weak signals and a good performance of detection of weak signals with different S/N ratio can be ensured under the optimized conditions.

Key words: Stochastic resonance algorithm, Periodic modulation, Weak signal detection, Laser Raman spectrum