摘要
藻类浮游颗粒对激光的散射和吸收是水下蓝绿激光通信性能在海水中衰减的主要原因。依据离散偶极子理论,建立了双椭球、四椭球、柱型丝状、环型丝状和S型丝状五种主要团聚核壳蓝藻颗粒模型,数值计算了核壳藻类粒子在532 nm蓝绿激光波段处的消光系数、吸收系数和散射系数随核壳蓝藻粒子尺寸的变化关系;基于均匀混合层理论,对比了有无中间混合层的核壳蓝藻模型的散射强度随散射角度的变化情况,计算了五种核壳蓝藻模型的粒子尺寸对其散射矩阵元素的影响。计算结果表明:五种藻类在蓝绿激光波段处的吸收系数和散射系数随粒子尺寸的增加而递增,且前向散射强度最大;随着散射角度的增加,五个模型的散射强度都在递减,几个大尺寸藻类模型的散射矩阵元素比值振荡较多。研究结果为海洋水下悬浮藻类颗粒的蓝绿激光散射特性和吸收特性的研究及水下蓝绿激光通信信道的建模提供了参考。
The laser scattering and absorption of algal particles is the main reason for the attenuation of underwater blue-green laser communication performance in seawater.In this paper,based on the discrete dipole theory,five kinds of particle models of agglomerated core-shell cyanobacteria are established,including double ellipsoidal,four ellipsoidal,columnar filamentous,ring filamentous,and S filamentous ones.The extinction absorption and scattering coefficients of the core-shell algae particles at 532 nm of the blue-green laser are calculated as a function of the size of the core-shell cyanobacteria particles.Based on the uniform mixed layer theory,the scattering intensities of the core-shell cyanobacteria models versus scattering angle with and without an intermediate mixed layer are compared,and the influence of particle size on the scattering matrix elements is calculated for the five core-shell cyanobacteria models.The calculation results show that the absorption and scattering coefficients of the five kinds of algae at the band of a blue-green laser increase with the increase of particle size,and the forward scattering intensity is the largest.In contrast,the scattering intensities of the five models decrease with the increase of scattering angle,and the scattering matrix element ratios of several kinds of large size algae models fluctuate more.These research results lay a foundation for the study of blue-green laser scattering and absorption characteristics of underwater suspended algae particles as well as the modeling of underwater blue-green laser communication channels.
作者
贺锦涛
王明军
张佳琳
He Jintao;Wang Mingjun;Zhang Jialin(Institute of Automation and Information Engineering,Xi'an University of Technology,Xi'an,Shaanxi 7100AS,China;School of Physics and Telecommunications Engineering,Shaanxi University of Technology,Hanzhong,Shaanxi 723001,China;Key Laboratory of Military-Civilian Joint Construction of Intelligent Collaborative Network of Shaanxi Province,Xi'an,Shaanxi 710126,China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2021年第17期165-172,共8页
Acta Optica Sinica
基金
国家自然科学基金重大研究计划培育项目(92052106)
国家自然科学基金(61771385)
陕西省杰出青年科学基金(2020JC-42)
固体激光技术重点实验室开放基金(6142404190301)
西安市高校人才服务企业工程项目(GXYD14.26)。
关键词
散射
蓝藻粒子
蓝绿激光
离散偶极子近似方法
散射矩阵
scattering
cyanobacteria particles
blue-green laser
discrete dipole approximation method
scattering matrix
