光子学报, 2018, 47 (2): 0228001, 网络出版: 2018-01-30
高分一号宽视场成像仪多场地高频次辐射定标
Multisite High-frequency Radiometric Calibration of GF-1 Wide Field of View
摘要
为了提升国产光学遥感卫星载荷的定标频次, 提出了一种基于国内多场地的高频次定标方法, 实现了高分一号(GF-1)宽视场成像仪(WFV)的高频次绝对辐射定标.介绍了基于多场地的高频次定标原理, 针对GF-1 WFV的工作参数和工作特点, 提出了国内定标场的优选原则, 并分析了定标场地表特性的时间稳定性.利用中分辨率成像光谱仪(MODIS)的地表和大气产品替代场地定标的现场观测数据, 增加了定标可用的数据量, 同时用实测数据对MODIS地表产品进行真实性检验.实现了GF-1 WFV的多场地高频次定标, 并将定标系数结果与官方定标结果进行比对验证.结果表明:基于国内多场地的高频次定标方法可以获得GF-1 WFV的时间序列定标系数, GF-1 WFV相机4的定标结果与官方定标结果具有较好的一致性, 各波段与官方定标结果的相对偏差分别为-0.49%、1.33%、-1.01%和3.86%.基于多场地的高频次定标方法可有效地提高国产卫星载荷的定标频次, 及时跟踪载荷的辐射特性变化.
Abstract
To increase the calibration frequency of Chinese optical remote sensing satellite sensor, a high-frequency calibration method based on domestic multisite was presented. And the in-flight high-frequency absolute radiometric calibration of GF-1 Wide Field of View (WFV) was conducted using this method. The theory of high-frequency calibration based on multisite was intruduced. The optimized selection principle of domestic calibration site was presented according to the parameters and characteristics of GF-1 WFV. And the temporal stability of site surface was analyzed. MODIS land and atmosphere products were used to instead of in-situ measurements to increase the amount of available calibration data. The validation of MODIS land product was conducted using in-site measurements. The high-frequency calibration of GF-1 WFV4 based on Chinese multisite was carried out, and the calibration coefficients were compared with the official calibration coefficients.The result shows that time series calibration coefficients of GF-1 WFV can be obtained using the multisite high-frequency calibration method. The calibration results of GF-1 WFV4 are in good agreement with the results of the official calibration. The relative differences of GF-1 WFV4 all bands calibration coefficients of the two methods are -0.49%, 1.33%, -1.01% and 3.86% respectively, which illustrates the availability of this method. The method can be used to improve the calibration frequency of Chinese remote sensing sensor, and timely track the changes of sensor.
韦玮, 张艳娜, 张孟, 赵春艳, 李新, 郑小兵. 高分一号宽视场成像仪多场地高频次辐射定标[J]. 光子学报, 2018, 47(2): 0228001. WEI Wei, ZHANG Yan-na, ZHANG Meng, ZHAO Chun-yan, LI Xin, ZHENG Xiao-bing. Multisite High-frequency Radiometric Calibration of GF-1 Wide Field of View[J]. ACTA PHOTONICA SINICA, 2018, 47(2): 0228001.