光谱学与光谱分析, 2014, 34 (3): 735, 网络出版: 2014-03-14
大气气溶胶光学厚度对天基光学遥感系统成像品质的影响
Effects of Aerosol Optical Thickness on the Optical Remote Sensing Imaging Quality
摘要
由于大气环境的变化, 大气气溶胶污染对光学遥感器成像品质的影响越来越受到载荷研制部门的重视。 天基光学遥感系统成像过程中, 受到大气气溶胶退化的影响使得光学遥感器成像品质的恶化。 大气导致图像质量降低主要原因之一是气溶胶混浊介质引起的前向光散射。 根据气溶胶辐射特性, 利用混浊介质辐射传输方程, 推导了包含气溶胶光学特性的大气点扩散函数模型。 根据此模型, 定量化分析与评价其对光学遥感器成像的大气模糊效应。 研究发现气溶胶介质除了对遥感器成像过程中大气透过率能量衰减影响外, 更重要的是由于散射对成像质量产生退化作用, 大气气溶胶光学厚度的增加使得气溶胶散射强度的增强, 气溶胶光学厚度的变化同样强烈的影响着点扩散函数的空间分布范围, 正是因为气溶胶在空间域内对图像产生的退化作用, 使得遥感图像质量降低, 尤其是图像清晰度的下降。 同时, 该模型也为遥感图像仿真中, 大气链路环节的优化与改进提供了参考依据与模型方法。
Abstract
In recent years, due to changes in atmospheric environment, atmospheric aerosol affection on optical sensor imaging quality is increasingly considered by the load developed departments. Space-based remote sensing system imaging process, atmospheric aerosol makes optical sensor imaging quality deterioration. Atmospheric medium causing image degradation is mainly forward light scattering effect caused by the aerosol turbid medium. Based on the turbid medium radiation transfer equation, the point spread function models were derived contained aerosol optical properties of atmosphere in order to analyze and evaluate the atmospheric blurring effect on optical sensor imaging system. It was found that atmospheric aerosol medium have effect on not only energy decay of atmospheric transmittance, but also the degradation of image quality due to the scattering effect. Increase of atmospheric aerosol optical thickness makes aerosol scattering intensity enhanced, variation of aerosol optical thickness is also strongly influences the point spread function of the spatial distribution. it is because the degradation of aerosol in spatial domain, which reduces the quality of remote sensing image, in particularly reduction of the sharpness of image. Meanwhile, it would provide a method to optimize and improve simulation of atmospheric chain.
胡新礼, 顾行发, 余涛, 张周威, 李娟, 栾海军. 大气气溶胶光学厚度对天基光学遥感系统成像品质的影响[J]. 光谱学与光谱分析, 2014, 34(3): 735. HU Xin-li, GU Xing-fa, YU Tao, ZHANG Zhou-wei, LI Juan, LUAN Hai-jun. Effects of Aerosol Optical Thickness on the Optical Remote Sensing Imaging Quality[J]. Spectroscopy and Spectral Analysis, 2014, 34(3): 735.