概括
双频激光雷达 (DFL) 克服了大气流,在测量风速方面表现优于单频激光雷达 (SFL). 在强的流和长距离中,DFL保持了准确性,使得精确的多普勒速度计算成为可能.
科学领域:
- 大气光学和遥感技术
- 激光物理与技术 激光物理与技术
- 气象学和流体动力学
背景情况:
- 大气流降低了激光相干度,阻碍了用于多普勒速度测量的传统单频LiDAR (SFL).
- 双频激光雷达 (DFL) 使用两个激光频率通过分析多普勒转移差异来测量风速.
- 流对DFL相位扰动和整体性能的具体影响仍然不完全理解.
研究的目的:
- 研究和量化大气流对双频LiDAR (DFL) 性能的影响.
- 为了确定双频相差的变异,作为DFL性能评估的关键指标.
- 为了比较DFL与SFL在减轻流引起的风速估计误差方面的有效性.
主要方法:
- 理论建模以确定双频相差的变量作为性能指标.
- 对相位扰动的定量分析与流强度,传播距离和频率差异相关.
- 在各种流条件和范围下对DFL和SFL的比较性能评估.
主要成果:
- 阶段扰动显示了与流强度,传播距离和双频差异的定量相关性.
- 与SFL相比,DFL显著减轻了大气流的影响.
- DFL实现了优越的速度估计误差性能,即使在强的流和长距离.
结论:
- DFL有效地克服了SFL系统固有的大气流局限性.
- 双频相差的偏差是评估DFL性能的一个关键因素.
- DFL能够准确地计算多普勒速度,具有良好的范围和速度分辨率,适用于风力测量.
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