Geometric Characteristics of the Early Products of ALOS PRISM



An orientation program developed for ALOS PRISM was applied to a triplet of the early product of ALOS PRISM to clarify the geometric characteristics of the sensor. Errors of single image observation were 1.0 km before adjustment. The geometric errors were likely caused by rotation of radiometers and by mis-alignment of CCDs on the focal plane. Adjusting the rotation of the radiometers, residuals of single image observation were 4.9 m in the horizontal, and residuals of triplet image observation were 2.9 m in the horizontal and 3.2 m in the vertical, respectively. East-west distributed control points are necessary to adjust the radiometer rotation, especially two pairs of east and west control points are recommended.


1. Introduction
2. Algorithm
3. Used data
  3.1 PRISM data
  3.2 Data extraction from level 1B1 product
  3.3 Known ground points
4. Results
  4.1 Before adjustment
  4.2 Shift of the principal positions
  4.3 Rotation of the radiometers
5. Discussion
  5.1 Residual after adjustment of radiometer rotation
  5.2 Comparison with other research
  5.3 Necessary number of GCP
6. Conclusions