High Resolution 1:10,000 scale Mapping Strategy of Multi ... - NDMA

• the perspective center of the center scan line (i.e., X, Y, and Z),
• the change of perspective centers along the orbit,
• the three rotations of the center scan line (i.e., omega, phi, and kappa), and
• the changes of angles along the orbit.
In addition to fitting the bundle of light rays to the known points, satellite block
triangulation also accounts for the motion of the satellite by determining the
relationship of the perspective centers and rotation angles of the scan lines. It is
assumed that the satellite travels in a smooth motion as a scene is being scanned.
Therefore, once the exterior orientation of the center scan line is determined, the
exterior orientation of any other scan line is calculated based on the distance of that
scan line from the center and the changes of the perspective center location and
rotation angles.
Bundle adjustment for triangulating a satellite scene is similar to the bundle
adjustment used for aerial images. A least squares adjustment is used to derive a set
of parameters that comes the closest to fitting the control points to their known
ground coordinates, and to intersecting tie points.
The resulting parameters of satellite bundle adjustment are: ground
coordinates of the perspective center of the center scan line rotation angles for the
center scan line coefficients, from which the perspective center and rotation angles
of all other scan lines are calculated ground coordinates of all tie points
Collinearity equation and satellite block triangulation
Modified collinearity equations are used to compute the exterior orientation
parameters associated with the respective scan lines in the satellite scenes. Each
scan line has a unique perspective center and individual rotation angles. When the
satellite moves from one scan line to the next, these parameters change. Due to the
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