The Underwater Communication Link(UCL)is a crucial component of Underwater Wireless Optical Communication(UWOC)systems,requiring optimised design to mitigate the high power attenuation inherent in seawater.To ensure t...The Underwater Communication Link(UCL)is a crucial component of Underwater Wireless Optical Communication(UWOC)systems,requiring optimised design to mitigate the high power attenuation inherent in seawater.To ensure the reliability of an optimal UCL design,it is essential to account for the three primary scattering regimes:forward scattering(FSC),backward scattering(BSC),and isotropic scattering(ISC)in seawater channels.This study introduces a new photon-tracking model based on a discrete equation,facilitating Monte Carlo Simulation(MCS)to evaluate how different scattering regimes influence received photon distribution.Three distinct Scattering Regime Contribution Weight(SRCW)probability sets were employed,each representing different UCL operational configurations dominated by specific scattering regimes.The proposed modeling approach enables a comprehensive assessment of the temporal characteristics of received optical pulses,channel loss,and time spread-ultimately defining the optimal UCL design parameters.The key findings of this study include:(1)Enhancing the FSC regime dominance leads to a quasi-light waveguide effect over link spans and small Fields of View(FOV)<25°,significantly improving channel performance in Harbor seawater compared to Coastal seawater.(2)A well-designed UCL with a small FOV(<25°)can minimise channel loss and time spread,ensuring high capacity and efficient performance in both Coastal and Harbor seawaters.(3)When BSC and ISC contributions exceed FSC dominance,the received optical pulse undergoes significant temporal broadening,particularly for larger FOV angles(>25°)and extended link spans.(4)The developed novel MCS-based discrete equation provides a simple yet robust model for simulating photon propagation in both homogeneous and inhomogeneous underwater channels.These insights contribute to developing more efficient and reliable UCL designs with military standards by enhancing UWOC system performance over a longer linkspan for a given limited optical power across various underwater environments.展开更多
设{X_n,-∞<n<∞}为独立同分布平方可积正值随机变量序列,u=EX_1,σ~2=VarX_1>0.记S_n=sum from X_i,T_n=T-n(X_1,…,X_n)是一统计量(或随机函数),可被表示为T_n=a_nS_n+R_n,其中a_n>0为常数序列,R_n为余项.该文证明若R_n=o...设{X_n,-∞<n<∞}为独立同分布平方可积正值随机变量序列,u=EX_1,σ~2=VarX_1>0.记S_n=sum from X_i,T_n=T-n(X_1,…,X_n)是一统计量(或随机函数),可被表示为T_n=a_nS_n+R_n,其中a_n>0为常数序列,R_n为余项.该文证明若R_n=o(a_nn^(1/2))a.s.,则对统计量T_n的乘积的几乎处处中心极限定理成立,且给出了它的渐近分布和弱不变原理.并以U统计量,Von-Mises统计量,线性模型误差方差的估计等几个常见的统计量为例说明结果应用的广泛性.推广了以往文献中关于独立同分布随机变量和的乘积及U统计量乘积的相应结果.展开更多
基金The Deanship of Scientific Research(DSR)at King Abdulaziz University(KAU),Jeddah,Saudi Arabia,has funded this project under Grant No.(KEP-PhD:72-130-1443).
文摘The Underwater Communication Link(UCL)is a crucial component of Underwater Wireless Optical Communication(UWOC)systems,requiring optimised design to mitigate the high power attenuation inherent in seawater.To ensure the reliability of an optimal UCL design,it is essential to account for the three primary scattering regimes:forward scattering(FSC),backward scattering(BSC),and isotropic scattering(ISC)in seawater channels.This study introduces a new photon-tracking model based on a discrete equation,facilitating Monte Carlo Simulation(MCS)to evaluate how different scattering regimes influence received photon distribution.Three distinct Scattering Regime Contribution Weight(SRCW)probability sets were employed,each representing different UCL operational configurations dominated by specific scattering regimes.The proposed modeling approach enables a comprehensive assessment of the temporal characteristics of received optical pulses,channel loss,and time spread-ultimately defining the optimal UCL design parameters.The key findings of this study include:(1)Enhancing the FSC regime dominance leads to a quasi-light waveguide effect over link spans and small Fields of View(FOV)<25°,significantly improving channel performance in Harbor seawater compared to Coastal seawater.(2)A well-designed UCL with a small FOV(<25°)can minimise channel loss and time spread,ensuring high capacity and efficient performance in both Coastal and Harbor seawaters.(3)When BSC and ISC contributions exceed FSC dominance,the received optical pulse undergoes significant temporal broadening,particularly for larger FOV angles(>25°)and extended link spans.(4)The developed novel MCS-based discrete equation provides a simple yet robust model for simulating photon propagation in both homogeneous and inhomogeneous underwater channels.These insights contribute to developing more efficient and reliable UCL designs with military standards by enhancing UWOC system performance over a longer linkspan for a given limited optical power across various underwater environments.
文摘设{X_n,-∞<n<∞}为独立同分布平方可积正值随机变量序列,u=EX_1,σ~2=VarX_1>0.记S_n=sum from X_i,T_n=T-n(X_1,…,X_n)是一统计量(或随机函数),可被表示为T_n=a_nS_n+R_n,其中a_n>0为常数序列,R_n为余项.该文证明若R_n=o(a_nn^(1/2))a.s.,则对统计量T_n的乘积的几乎处处中心极限定理成立,且给出了它的渐近分布和弱不变原理.并以U统计量,Von-Mises统计量,线性模型误差方差的估计等几个常见的统计量为例说明结果应用的广泛性.推广了以往文献中关于独立同分布随机变量和的乘积及U统计量乘积的相应结果.
