摘要
针对海洋信道中多重散射导致的以脉冲响应为特征的激光脉冲时延展宽问题,采用蒙特卡罗模拟方法和Gamma函数,构建了水下无线激光传输脉冲响应模型。分析海水的光学特性,提出一种多Gamma函数模拟水下信道脉冲响应的闭合表达式。理论分析和建模结果表明:该模型采用4个Gamma函数表示激光脉冲在水下的传输过程,即由于散射作用强弱差异产生的4条长度不同的路径。其中前3条以散射级数低、光程较短的准弹道光路径为主,最后1条为散射级数高且多重散射光占主体的路径。同时通过对比验证了所提模型的准确性和优异性,采用该模型对不同系统参数下激光传输脉冲响应进行建模,其结果很好地描述了激光脉冲水下散射特性和脉冲时延展宽特性。
Considering the broadening of the laser pulse time delay caused by multiple scattering in ocean channels,we investigate the modeling of underwater wireless laser pulse responses using Monte Carlo simulations and Gamma functions.Seawater optical characteristics are analyzed,and a closed-form expression of a multi-Gamma function is proposed to simulate the impulse response in underwater channels.The theoretical analysis and modeling results show that the model uses four Gamma functions to represent laser pulse transmission under water,i.e.,four paths with different lengths generated owing to the difference in the scattering intensity.The first three paths are mainly quasi-ballistic light paths with low scattering series and short optical path,whereas the last one presents a high scattering series and multiple scattered light.Simultaneously,the model accuracy and superiority are verified via comparison,and the proposed method is used to simulate the impulse response of laser transmission under different system parameters.The obtained results well describe the laser pulse scattering characteristics and time delay broadening under water.
作者
李天松
阳荣凯
高翔
黄艳虎
Li Tiansong;Yang Rongkai;Gao Xiang;Huang Yanhu(School of Information and Communication,Guilin University of Electronic Technology,Guilin,Guangxi 541004,China;Guangxi Key Laboratory of Precision Navigation Technology and Application,Guilin,Guangxi 541004,China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2019年第11期1-11,共11页
Acta Optica Sinica
基金
国家自然科学基金(61561014)
广西精密导航技术与应用重点实验室(DH201709)
桂林电子科技大学研究生科研创新项目(2018YJCX36)
