THE CALIBRATION PROCEDURE OF THE MULTISPECTRAL IMAGING INSTRUMENTS ON BOARD THE RAPIDEYE TM REMOTE SENSING SATELLITES

: RapidEye operates five spacecraft within a constellation. Each spacecraft accommodates an identical multispectral pushbroom imager as the payload. RapidEye has the capability to view any place on Earth and capture up to 4 million km 2 of image data on a daily basis. The key business interests of RapidEye are agricultural and cartographic products and services, however, the advantages of the RapidEye System are widespread over various thematic applications (e.g. pipeline monitoring, medium scale mapping, disaster monitoring and many others). To maximise the systems capabilities, all five instruments have to have the same radiometric response behavior and the same geometric properties. To achieve this goal, RapidEye applies a dedicated calibration concept to optimize the spectral and geometric homogeneity across all the imagers over the foreseen mission lifetime. This will be achieved by a spatial and a temporal calibration for the radiometric corrections and geometric adjustments using both camera alignment and scale calibration and camera focal plane calibration. This paper mainly describes the concepts used for the relative and absolute radiometric calibration of the five multispectral imagers but also briefly describes the geometric part of the calibration.