“实践九号”A卫星图像的直接解调成像方法

Direct Demodulation Method Applied in Remote Sensing Images of SJ-9A Satellite

"实践九号"(SJ-9)卫星是中国新技术试验卫星系列规划中的首发星,其中A星搭载的光学成像有效载荷技术试验项目为高分辨率多光谱相机,其图像数据将应用于国土资源调查与监测、农林业、环境保护、防灾减灾等领域,满足用户对高分辨率数据的需求。目前,遥感数据地面处理主要使用美国学者提出的调制传递函数补偿方法,而该文使用了中国科学家自主提出的直接解调成像方法处理"实践九号"A卫星全色谱段的遥感图像。通过分析处理前后的敦煌靶标和法国靶标的调制传递函数(Modulation Transfer Function,MTF)和点扩散函数,认为经直接解调成像方法处理后的图像清晰度和MTF有明显提高,达到了国际上同类遥感图像处理方法的先进水平。

SJ-9A satellites are the Chinese first two technical test satellites of the SJ satellite series, of which the SJ-9A satellite carries a high resolution multispectral camera. The remote sensing images of sJ-gA satellite will be used in land resource survey and monitoring, agriculture and forestry, environmental protection, disaster prevention and mitigation, and so on. In this paper, direct demodulation （D-D） method which is put forward by Chinese scientists is used in full-color remote sensing image restoration of SJ-9A satellite. By analyzing the MTF and PSF of Dunhuang target image and French target image before and after processing, it is shown that the image definition and MTF processed by D-D method are improved greatly. D-D method could enhance the quality of full-color remote sensing images and it has reached a high level of remote sensing image restoration methods.