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基于大气通道互惠的光学自适应功率控制,以减轻自由空间光学通信中的流干扰

Haifeng Yao, Weihao Wang, Chang Zhou

|November 29, 2023

概括

本研究介绍了用于自由空间光通信的自适应功率控制系统,以应对大气流. 该系统显著减少信号扭曲,提高数据可靠性,提高通信性能.

科学领域:

光学通信是指光学通信.
信号处理信号处理
大气物理学大气物理学

背景情况:

自由空间光通信 (FSOC) 系统由于大气动荡而遭受信号退化,导致强度闪和比特错误率 (BER) 的增加.
现有的减缓技术往往缺乏实时适应性,或者在动态大气条件下实施起来很复杂.

研究的目的:

开发和验证FSOC系统的连续时间域自适应功率控制 (OAPC) 模型.
为了减轻接收器光学强度闪和BER恶化使用大气流道互惠.
在不同流条件下提高FSOC链路的稳定性和可靠性.

主要方法:

提出了一个发射器光学自适应功率控制 (OAPC) 系统架构,利用四波长的光学信号和利用大气流道互惠.
使用电子可变光学减弱器 (EVOA) 和辅助纤维放大器 (EDFA) 进行功率调整.
开发了一种对- (G-G) 信号的互惠性评估模型,使用自回归移动平均 (ARMA) 随机过程,考虑延迟和噪声.
在各种流,噪声和采样不匹配的情况下模拟信号互惠率和闪指数 (SI).
融合时间域信号 (QAM-16,QAM-32) 与G-G互动流信号来分析概率密度函数 (PDF) 和OAPC后的BER纠正.
使用大气流模拟器进行了64 Gbps QAM-16 OAPC通信实验.

主要成果:

该OAPC系统有效地使用基于毫秒采样延迟的互惠性来抑制光强度闪.
信号与噪声比 (SNR) 显著改善,在强动荡下抑制更为明显.
总体而言,BER的减少超过了2.8个数量级,在某些情况下达到6个数量级,特别是随着接收功率的增加.
在动荡环境中证明了FSOC实时自适应信号处理的可行性.

结论:

拟议的OAPC系统基于大气通道互惠性,为减轻闪光和改善FSOC的BER提供了强大的解决方案.
这项工作为FSOC中先进的自适应信号处理算法提供了基础,包括自适应编码,通道估计和光学波面控制.
实验验证证证实了OAPC方法在现实流条件下的实际适用性和显著的性能增长.

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