Study On Scattering And Absorption Characteristics Of Blue-green Laser Of Typical Marine Suspended Aggregate Particles

Marine suspended aggregate particles have important research significance in underwater blue-green laser communication,seabed exploration,marine lifesaving and submarine warfare.There are many suspended particles in the real seabed,and the structure is complex,which leads to a large number of blue-green laser energy attenuation in the underwater blue-green laser communication process,resulting in the improvement of the bit error rate in the communication process.Therefore,it is of great research value to study the scattering and absorption characteristics of blue-green laser by marine suspended particles.Marine suspended particles can be roughly divided into two categories,namely,non-pigmented marine suspended particles and marine planktonic algae particles.In this paper,a large number of marine suspended particles agglomeration models are established according to relevant documents,and the blue-green laser scattering and absorption characteristics of the above models are studied and analyzed by using the discrete dipole theory.The research contents are as follows:1.Several non-pigmented Marine suspended particle models were established,and the effects of the number of non-pigmented Marine suspended particle,the size of non-pigmented Marine suspended particle and the agglomeration type on the scattering,absorption and extinction coefficients of the model were discussed.2.Considering the influence of Marine suspended algae on underwater blue-green laser communication,a single algae model,three single algae aggregate models and four single algae aggregate models were established,and the effects of the size of single algae particles on the scattering,absorption and extinction coefficients of the above single algae models were studied.The effect of intermediate mixing layer on the scattering intensity of single algae agglomeration model was considered.3.Considering the complex composition of Marine aggregated phytoplankton,several filamentous algae models and filamentous algae models were established,and the scattering,absorption and extinction coefficients of the above filamentous algae models were studied.The numerical results show that the suspended particles of pigment model with the increase of particle size of each model scattering,absorption and the extinction coefficient increment,different size of pigment particles scattering intensity with the increase of scattering Angle decreased,the large size of the scattering intensity of particle model is greater than the scattering intensity of small size particles.The scattering,absorption and extinction coefficients of Marine phytoplankton models increase with the increase of particle size,and the scattering coefficients increase with the increase of model size.The scattering intensity of the phytoplankton model with uniform mixing layer is greater than that of the phytoplankton particle model without intermediate mixing layer,and the scattering intensity of each model decreases with the increase of scattering Angle.The scattering intensity of large size Marine phytoplankton mostly concentrates in the forward scattering region,and the minimum value of lairge size agglomerated particles mostly exists in the backscattering region.The scattering matrix ratio of Marine phytoplankton mostly has many oscillations,and the oscillations in the backscattering region become more intense with the increase of model size.