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Updated: Jul 22, 2025

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对于宽带极化激光雷达技术的分子脱极化比率的理论和实验研究

Zheng Kong, Xinglong Yang, Liang Mei

|July 21, 2023

概括

这项研究修订了分子去极化比率 (MDR) 模型用于极化激光器,考虑了卡班尼斯线路传输率和宽带激光源. 结果显示MDR计算中的显著偏差,突出了用于激光雷达测量验证的准确建模的重要性.

科学领域:

大气光学是大气光学.
遥感遥感遥感遥感
利达尔技术利达尔技术

背景情况:

分子去极化比 (MDR) 对于验证极化激光雷达测量准确度至关重要.
之前的MDR模型主要考虑了窄带激光线宽,并假设恒定的Cabannes线传输率.
这些假设可能导致不准确,特别是在宽带光源或波长转移时.

研究的目的:

通过纳入Cabannes线路传导率,重新检查MDR的窄带理论模型.
开发和验证适用于使用多模激光二极管的极化激光雷达的MDR宽带理论模型.
评估激光线宽,接收带宽和波长偏移对MDR计算的影响.

主要方法:

重新检查窄带MDR理论模型以包括Cabannes线路传输率.
为MDR开发一种新的宽带理论模型.
模拟研究分析MDR与各种激光和接收器参数之间的关系.
使用基于520nm成像的偏振激光器进行实验验证.

主要成果:

窄带模型显示偏差超过200%,波长偏移为0.5纳米,收音带宽为0.5纳米,波长偏移为532纳米.
宽带模型表明,MDR受到激光线宽,接收带宽和波长转移的显著影响.
模拟显示,宽带模型计算的MDR比当带宽匹配时忽略激光线宽的MDR高21%.
实验验证表明,理论MDR (0.132) 和测量体积去极化比 (0.129±0.0025) 之间有很好的一致性.

结论:

准确的Cabannes线路传导率建模对于极化激光雷达中精确的MDR计算至关重要.
提出的宽带理论模型准确地评估了使用多模激光二极管的激光雷达系统的MDR.
这项研究证实了基于成像的极化激光雷达的高测量精度和宽带模型的可行性.

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