贝塞尔-高斯束通过科尔摩戈罗夫流传播的平均强度与二次结构函数的二次结构函数
概括
贝塞尔-高斯束在流中保持其形状,为光学无线通信提供优势. 这项研究提供了一种简化的方法来计算它们在大气条件下的性能.
科学领域:
- 光学物理和大气光学.
- 专注于随机介质中的光束传播.
背景情况:
- 贝塞尔-高斯 (BG) 束以其在自由空间中的非衍射传播而闻名.
- 它们在动荡大气中的表现仍然是一个活跃的研究领域.
- 现有的方法,如扩展的惠根斯-弗雷内尔 (EHF) 原理,产生复杂的表达式.
研究的目的:
- 在科尔摩戈罗夫流中获得BG光束平均强度的闭式表达式.
- 为分析BG光束通过大气流传播提供一种可操作的方法.
- 评估用于光学无线通信 (OWC) 的BG光束.
主要方法:
- 使用二次结构函数 (QSF) 假设进行流建模.
- 平均强度表达为自由空间强度和点差函数 (PSF) 的卷积积分.
- 将卷积积分缩小到一个单一的,可评估的单维积分.
主要成果:
- 导出了BG束在弱和强流动中的平均强度的封闭式表达式.
- 获得了光束的根平均平方 (rms) 宽度的一维积分表示.
- 衍生的表达式很容易被评估和绘制.
结论:
- 该研究提供了一个简化的分析工具,用于理解大气流中BG束传播.
- 这些发现有助于对BG光束进行评估,用于OWC等实际应用.
- 这项工作简化了在随机介质中复杂的传播计算.
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