Simulation of stochastic resonance in underwater laser communication

Due to the light attenuation caused by absorption and scattering of sea water, the performance of underwater optical communication system is limited. Usually, the optical signals will be decayed severely in hundreds of meters and the waveforms are submerged in noise. To improve the signal-to-noise ratio (SNR), for traditional methods, most of the noise can be suppressed by filters based on classic linear theory. However, the signal will also be relatively attenuated by the filters. In this research, the nonlinear signal processing method, named as stochastic resonance (SR), is introduced to enhance the underwater laser communication signal. A SR system is simulated to evaluate the feasibility and effectiveness of weak signal detection in underwater laser communication. The influence of the noise to the bit-error-rate(BER) and the parameter optimization are simulated and discussed. It is proved that, the SR system has advantage over the low-pass filter(LPF) and has promising prospect in the signal enhancement in underwater laser communication.