Interferometry begins with two processed SAR complex images. We first line up the images to sub-pixel precision, and then subtract the image phases. This phase difference image is referred to as an interferogram.
Register_sic accomplishes each of these tasks, starting from two single-look, processed SAR complex images. These pieces then lined up to single-pixel accuracy by resolve, then lined up to sub-pixel accuracy by fico. Once the sub-pixel offsets are determined, the second image is resampled to line up with the first by remap.
Since the images are not necessarily processed to the same doppler, and resampled outside of the processor, register_sic generally has slightly lower coherence than register_ccsd.
Once the images are lined up, the phase of the second image is subtracted from that of the first (in igram), and an interferogram is born. This interferogram can then be further analysed with your own software, or turned into a DEM with tandem_ifm.
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Last Updated: September 1, 1998
If you have any questions, please feel free to email olawlor@acm.org