Improvement of a Monte-Carlo-simulation-based turbulence-induced attenuation model for an underwater wireless optical communications channel

Abstract

The light propagating in an underwater wireless optical communications (UWOC) channel suffers absorption and scattering effects jointly caused by particles and turbulence. By using Monte Carlo simulation (MCS), most of the research involving UWOC channel modeling has sufficiently considered the attenuation caused by particles while ignoring or erroneously considering the absorption and scattering effects induced by turbulence, which will result in an underestimation of attenuation. Motivated by this, we use a MCS method to construct a more complete and more reasonable channel model, which makes up for the deficiencies of previous studies and provides a general analysis framework for the absorption and scattering effects brought by the two factors of particles and turbulence. We further study the path loss, channel impulse response (CIR), and probability density function (PDF) of the light intensity under different communication scenarios. Results show that, compared to the situation involving only particle effects, the addition of consideration of turbulence effects increases the path loss by more than 5 dB, reduces the CIR amplitude to less than one-third, and makes the light intensity PDF become more dispersed. Our research can provide certain theoretical guidance for UWOC system design and performance evaluation.