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This paper starts from defining the relative equations between
the ground space and the image space, based on two
radargrammetric conditions when the image is formed by the side-
looking airborne radar system, furthermore, analyzing and
studying for the mathematical model. The experimental data are
two SAR images with opposite side-looking in the Chao-chou area,
Pintung County. These two images are digital complex images, and
the digital number is obtained from the number of the scan lines
in the azimuth direction and the sample number in the range
direction. Since the exterior orientation and the flight speed
of the radar antenna carrier is time-varying, one goal of this
paper is to find a mathematical model in order to define the
time-varying characteristic. On the single SAR image , we used
different order polynomials to describe the changes of dynamic
exterior orientation and squint angle of SAR carrier , and then
the track of the airborne carrier is solved by the mixed
adjustment, therefore the three-D spatial coordinates of the 16
conjugate check points on two SAS images can be set up according
to these data. The root mean square error of the ground
conjugate points can be at the level of 7-8 m horizontally and
9m vertically ,if the solution is solved by the intersection of
two images. With such an considerable improvement compared to
the earlier researches, the mathematical model set up by this
research is stated clearly in the following text.
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