General Stochastic Channel Model and Performance Evaluation for Underwater Wireless Optical Links
General Stochastic Channel Model and Performance Evaluation for Underwater Wireless Optical Links
复制标题
水下无线光链路通用随机信道模型及性能评估
DOI：
10.1109/twc.2015.2485990
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发表时间：
2016-02-01
影响因子：
10.4
通讯作者：
Dong, Yuhan
中科院分区：
文献类型：
--
作者：
Zhang, Huihui;Dong, Yuhan
在水下无线光通信（UWOC）中，吸收和散射是链路特性的特征，因为光子在与水分子或悬浮颗粒相互作用时可能会经历这两个过程，分别产生能量损失和方向改变。在这项工作中，我们考虑了吸收和散射对概率分布的影响，即，光子在空间和时间域中的归一化强度分布。我们先前的工作提出了一个随机信道模型来表示传播光子的时空概率分布仅为非散射和单散射组件的UWOC链接。然而，在通信距离较长和/或水体类型较浑浊的水下环境中，多次散射将主导散射行为。在这项工作中，我们考虑到所有三种类型的组件，包括非散射，单次和多次散射，并提出了一个更一般的随机信道模型，适合在混浊的水环境，如沿海和港口水域的Monte Carlo模拟。基于所提出的信道模型，我们还评估了UWOC链路的路径损耗，散射丰富度和衰减的性能。数值结果表明，多重散射可以补偿传统方法高估的路径损耗。此外，随着链路范围的增加，散射丰富度和衰减倾向于增加，但具有相反的效果，分别提高和降低高阶散射光子的接收概率。
In underwater wireless optical communications (UWOC), absorption and scattering characterize the link properties since photons may suffer these two processes with energy loss and direction change, respectively, when interacting with water molecules or suspended particles. In this work, we consider the effects of absorption and scattering on the probability distribution, i.e., normalized intensity distribution, of photons in space and time domains. Our prior work proposed a stochastic channel model to represent the spatial-temporal probability distribution of propagated photons only for nonscattering and single scattering components of UWOC links. However, multiple scattering will dominate the scattering behavior of the underwater environment with long communication distance and/or more turbid water type. In this work, we take into account all three types of components including nonscattering, single and multiple scattering, and present a more general stochastic channel model which fits well with Monte Carlo simulations in turbid water environment such as coastal and harbor water. Based on the proposed channel model, we also evaluate the performance of path loss, scattering richness, and attenuation of UWOC links. Numerical results suggest that multiple scattering can compensate the path loss overestimated by traditional approaches. Furthermore, scattering richness and attenuation tend to increase but have opposite effects to raise and reduce the received probabilities of higher order scattered photons, respectively, as link range increases.