Wang Zixiong, Zhong Wen-De, Yu Changyuan, Fu Songnian
School of Electrical and Electronic Engineering, Nanyang Technological University, 637353, Singapore.
Opt Express. 2012 Apr 9;20(8):9284-95. doi: 10.1364/OE.20.009284.
In this paper, we analytically investigate an optical signal detection scheme to mitigate the scintillation effect with the assistance of a co-propagating reference continuous wave (CW) light. Using the correlation coefficient between the intensities of the data light and the reference CW light, we mathematically derive their joint intensity distributions under two widely used atmospheric turbulence channel models, namely log-normal distributed channel model and Gamma-Gamma distributed channel model, respectively. We also carry out the Monte-Carlo (MC) simulation and show that theoretical results agree with simulation results well. Our analytical results reveal that when the correlation coefficient is 0.99, the power reductions to achieve BER of 10⁻³ are 12.3 dB and 20.4 dB under moderate and strong atmospheric turbulence conditions (i.e., Rytov variances of 1.0 and 4.0), respectively. In addition, the feasibility of the scheme applied to wavelength-division-multiplexed (WDM) free-space-optical (FSO) transmission systems is also investigated, where only a single reference CW light could be used to mitigate the scintillation effects on all WDM channels.
在本文中，我们通过解析研究一种光信号检测方案，借助同向传播的参考连续波（CW）光来减轻闪烁效应。利用数据光和参考CW光强度之间的相关系数，我们分别在两种广泛使用的大气湍流信道模型下，即对数正态分布信道模型和伽马-伽马分布信道模型下，从数学上推导了它们的联合强度分布。我们还进行了蒙特卡罗（MC）模拟，并表明理论结果与模拟结果吻合良好。我们的分析结果表明，当相关系数为0.99时，在中等和强大气湍流条件下（即Rytov方差分别为1.0和4.0），实现误码率为10⁻³所需的功率降低分别为12.3 dB和20.4 dB。此外，还研究了该方案应用于波分复用（WDM）自由空间光（FSO）传输系统的可行性，其中仅使用单个参考CW光即可减轻对所有WDM信道的闪烁效应。
