高光谱激光雷达谱位合一的角度效应分析

高光谱激光雷达以其谱位合一的技术优势为实现超三维精准遥感观测提供了可行途径,因此成为当前激光雷达与高光谱遥感领域共同大力推进的前沿发展方向。目前已有多型原型系统研发出来并得到了原理性验证,然而针对其数据处理核心环节问题的基础技术仍较为欠缺。典型问题之一是不同波段回波信号受激光入射角度的影响,该角度效应限制了高光谱激光雷达实现高性能遥感。以芬兰空间信息研究所高光谱激光雷达原型系统扫描桦树树干为例探讨了该角度效应,发现了不同激光波段对不同入射角度的回波强度响应模式,推导出了角度效应的基本规律及其精细尺度的统计规律,为后续该方向的系统研发、数据处理及信息提取等提供了可借鉴的底层机理与技术基础。

Exploration of the Angular Effect in Hyperspectral LiDAR Spectrum-Location-Synchronous Data Collection

Hyperspectral Light Detection And Ranging(LiDAR) is a research direction that is being passionately advanced by both of the communities of LiDAR and hyperspectral remote sensing，because this frontier technology is of high potential for providing a feasible way to realize the beyond-3D RS.Some prototype systems have been developed and principally validated，but，so far，the fundamental technologies aiming at the core circles of its functioning are still in shortage.One of the representative circles is that the backscatting signals of different spectral bands are affected by the incidence angles of lasers，and this angular effect restricts hyperspectral LiDAR from achieving high-performance RS.In order to better grasp this angular effect that is caused by the morphology of object surfaces impacting the spectrum-location-synchronous data collection，this study explored its underlying characteristics，in the case of applying the Finnish Geospatial Research Institute-constructed hyperspectral LiDAR prototype system for measuring the trunk of a Birch tree.The rules of its different spectral bands responding to different laser incidence angles were analyzed and deduced，e.g.，for all of the spectral bands，their angular effects become weakening along with the laser incidence angles increasing.The findings of this study can provide new knowledge about the underlying mechanism of the angular effect，in favor of the following hyperspectral LiDAR researches on system development，data processing，and information derivation.