遥感辐射定标解决方案

概述与原理
解决方案
资料库

在遥感领域,辐射定标对遥感工作的结果非常重要,遥感用的光谱成像系统需要定期标定。

辐射定标的原理

?反射率法:

在卫星过顶时同步测量地面目标反射率因子和大气光学参量(如大气光学厚度、大气柱水汽含量等)然后利用大气辐射传输模型计算出遥感器入瞳处辐射亮度值。

具有较高的精度。

?辐亮度法:

采用经过严格光谱与辐射标定的辐射计,通过航空平台实现与卫星遥感器观测几何相似的同步测量,把机载辐射计测量的辐射度作为已知量,去标定飞行中遥感器的辐

射量,从而实现卫星的标定,最后辐射校正系数的误差以辐射计的定标误差为主。仅仅需要对飞行高度以上的大气进行校正,回避了底层大气的校正误差,有利于提高精度。

辐照度法:

又称改进的反射率法,利用地面测量的向下漫射与总辐射度值来确定卫星遥感器高度的表观反射率,进而确定出遥感器入瞳处辐射亮度,。这种方法是使用解析近似方法来计算反射率,从而可大大缩减计算时间和计算复杂性。

辐射定标的分类

辐射定标按照定标位置不同可分为三类,分别是实验室定标、机上和星上定标、场地定标

解决方案

光傲科技提供从实验室到现场的各种定标用辐射度计、标准灯、靶标用于遥感领域的光谱辐射定标,波长范围覆盖从紫外到中远红外波段。

  • 成像光谱仪的系统响应校正:采用OL 750 探测器光谱响应测试系统,对成像光谱系统对不同波段波长的灵敏度进行精确测定
  • 全系列积分球均匀光源提供最高精度、追溯 NIST 的光谱辐射亮度标准源,亮度可调,实现对成像光谱仪的系统定标,以及线性测试
  • 最全系列的光谱辐射照度标准灯,实现辐射照度法的辐射定标传递。
  • 提供各种遥感靶标,覆盖从紫外可见波段到中远红外
  • 提供漫反射涂层,用于制作大面积野外遥感靶标
  • 便携式光谱辐射度计,用于野外现场的辐射定标

特别推荐: OL 756 是全球唯一可以便携使用的双单色仪结构光谱辐射度计!

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Example 36" square target using grey Avian D, nominal 30% reflectance

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