重复轨道SIR-C极化干涉SAR数据植被覆盖区土壤水分反演研究

从理论和试验方面对图像的噪声评估方法进行了分析。结合北京1号小卫星特性, 进行了该类方法应用效能的评价, 讨论了分块评估噪声方法的最佳参数设置。选取满足噪声评估环境的图像, 实现了综合不同地表覆盖条件的北京1号小卫星图像噪声的评估。噪声评估结果与在轨测试情况的对比表明, 北京1号小卫星经过近3年的运行, 仍保持了较好的性能。

The inversion method study of sub-canopy soil moisture estimation using repeat pass SIR-C PolInSAR data

Noise estimation plays significant role in payload assessment, image processing and data application. In this paper, considering characteristics of Beijing-1 small satellite,the the image-based noise estimation methods with their applicabilityy are appraised in theories considering characteristics of Beijing-1 small satellite and , their performances are compared and analyzed through experiments,. and Tthe parameters and model optimization are also also discussed for better assessment of noise. for accurate estimation of the noise. Synthetic With comprehensive analysis of noise estimation results from different land cover types, the Beijing-1 small satellite noise estimation of Beijing-1 small satellite is evaluated with its standard deviation.conducted with carefully selected images and from different land cover types. Comparison of the noise estimation from images acquired in 2008 and the in-orbit test right after launch in 2005 shows that noise level of the Beijing-1 small satellite does not change, the satellite has well-kept performance even after 3 years of operation.