Uncertainty analysis of cross-calibration for HJ-1 CCD camera

Radiometric calibration of sensor is the basis of quantitative remote sensing, and uncertainty analysis is critical to ensure the accuracy of cross-calibration. Therefore, firstly, cross-calibration formulas were improved by redefining calibration coefficient and spectral band matching factor. In these formulas, c (ci) was redefined as the calibration coefficient of normalized apparent reflectance, and spectral band matching factor as the ratio of normalized apparent reflectance. Secondly, based on the contrast of ideal and actual conditions in cross-calibration, 8 sources of cross-calibration uncertainty were proposed: calibration uncertainty of standard sensor; pixel matching uncertainty; spectral band matching factor uncertainty caused by site altitude setting error, atmospheric parameters setting error, surface spectrum source, surface bidirectional reflectance characteristic, and error of atmospheric radiative transfer model; and uncertainty caused by other factors which were not considered. Finally, the contribution of each uncertainty was further analyzed and discussed for the HJ-1 CCD camera. The results provide many valuable references for evaluating the feasibility of alternative cross-calibration measurements.