부산대학교 도서관

The stability of the SWIR detector area array of the satellite-borne Hyperion hyperspectral system was investigated using six dates of cloud-free imagery collected from the Mount Fitton test site in South Australia. This test site was selected because of its mineralogical diversity, excellent geological exposure and relatively unchanging surface properties. Several aspects of Hyperion's SWIR stability were examined. First, as Hyperion comprises an area array detector of 256 pixels by 242 bands, the nature of any column (along-track) striping was tested. This striping is revealed when the dominating effects of topographic illumination and surface albedo are removed and comprises a minor component of scene-independent column-striping and a major component of scene-dependent striping. Based on scene-derived pixel-band statistics, it was found that both an applied shift and gain for each detector element was required to effectively remove this striping. Scene statistics were generated using scene lengths of 185 km (6170 lines) and 42 km (1400 lines) for comparative purposes. This showed that scene heterogeneity was strongly apparent in the 42 km length scene and only weakly apparent in the 185 km length scene. However, after generating and applying scale and offset corrections to the data, the resultant pixel spectral showed minimal change though the effect of removing the line striping was dramatic in the resulting imagery. Pixel spectra and mineral maps show near identical patterns for all dates of imagery validating the success of the Hyperion system, calibration and destriping process.