时间变化的传播模型和动态反相校正,用于在大气流中多重轨道角动量束的多重轨道角动量束
Optics express
|April 4, 2024
概括
一个新的模型解释了自由空间光通信中的时间变化的大气动荡. 优化的动态相位校正周期显著提高了多重轨道角动量束的传输效率.
科学领域:
- 光学通信是指光学通信的应用.
- 大气物理大气物理学
背景情况:
- 户外自由空间光学 (FSO) 通信受到大气流 (AT) 的阻碍.
- 之前的轨道角动量 (OAM) 传播模型没有完全解决AT的时间变化 (TV) 性质,特别是在横向风条件下.
研究的目的:
- 开发一种新的时间变化的多重复合OAM传播模型,该模型包含横向风下的大气流.
- 确定最佳的动态校正时间,以提高FSO通信系统的传输效率.
主要方法:
- 利用泰勒结-流假设来引入受横向风影响的AT相屏幕.
- 采用角光谱传播分析方法来建模多重OAM光束的时间和空间特征.
- 分析了有效的OAM相位校正时间,以获得优化的动态校正时间.
主要成果:
- 这项研究揭示了低级与高级OAM模式在弱与强的电视AT中具有明显的功率标准偏差行为.
- 确定了优化的动态校正周期,在预期错误校正限制内实现比特错误率 (BER).
- 在中度的TV AT下,0.18秒的校正周期显示了低计算负载 (实时校正的6%) 和高效率.
结论:
- 建立电视传播模型对于理解AT对多重OAM光束的影响至关重要.
- 一个优化的相位校正机制有效地减轻了电视AT造成的性能下降.
- 该研究通过解决动态大气影响,提高了FSO通信系统的整体传输效率.
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