Comparison of Spectral Characteristics between EO-1 ALI and IRS-P6 LISS-III Imagery

Data from the Indian Remote Sensing Satellite (IRS) P6 have been widely used for integrated land and water resources management. To complement and substitute data measured from other similar satellites and obtain constant measurements of the Earth's surface features, we evaluated the spectral characteristics between IRS-P6 LISS-III, a sensor of IRS P6, and EO- 1 ALI by comparing their top-of-atmosphere (TOA) reflectance and normalized difference vegetation index (NDVI) of three nearly simultaneous image pairs. In particular, due to the difference in NIR band design between LISS-III and ALI, the spectral characteristics of NIR band of LISS-III were compared with the two NIR bands of ALI. The results demonstrate that a distinct linear correlation exists between the spectral characteristics of LISS-III and ALI, with R² values ranging from 0.976 to 0.995 for TOA reflectance and from 0.992 to 0.997 for NDVI. Therefore, a mutual complementation and substitution of the TOA reflectance and NDVI between LISS-III and ALI images is feasible. Moreover, both TOA reflectance and NDVI of LISS-III are more similar to those of ALI at band 4 than to those of ALI at band 4P due to the difference in the two NIR bands of ALI.