A Rigorous Model for Spaceborne Linear Array Sensors

A rigorous sensor model for the georeferencing of imagery from CCD linear array sensors with along-track stereo viewing is presented. The model is based on the classical collinearity equations, which are extended for the specific characteristics of the acquisition of CCD linear scanners. It includes the sensor position and attitude modeling with second-order piecewise polynomials depending on the acquisition time and a self-calibration for the correction of radial and decentering lens distortions, principal point(s) displacement, focal length(s) variation and CCD line(s) rotation in the focal plane. Using well-distributed GCPs and, additionally, Tie Points (TPs), the external orientation and self-calibration parameters, together with the TPs ground coordinates, are estimated in a least-square adjustment. In order to demonstrate the flexibility of the model, stereo images from pushbroom sensors with different characteristics have been oriented with sub-pixel accuracy in the checkpoints. The results are presented and discussed.