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oversampling and multi-looking
Added by Igor Babayants about 1 month ago
Hello!
slc_ovr: you recommended for non-IPTA application used factor 2 in range and 1.5 in azimuth.
For IPTA - factor 2 in both directions.
What will be the result for processing, if used slc_ovr with factor 2 in range and azimuth, and then used even factor for multi-looking (2, 4 etc.)? Or main reason consist of used odd multi-look factors (3, 5...)?
Thanks!
Replies (2)
oversampling and multi-looking - Added by Charles Werner about 1 month ago
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Hello,
SLC oversampling is required if you have even multilooking factors. Oversampling
is required to make sure that the interferogram is not under sampled.
The Interferogram should be oversampled in azimuth and range with the factors
you mentioned.
the multi-looking factors do not change the decimation of the image, rather, the
interferogram appears smoothed. The multi-looking kernel is applied to the
interferogram without subsampling. or decimation.
Best regards,
Charles
On 01.07.2025 11:09, Igor Babayants wrote:
GAMMA Questions - SAR Data Preprocessing: oversampling and multi-looking
<https://dep1doc.gfz.de/boards/19/topics/663>/Igor Babayants/
Hello!
slc_ovr: you recommended for non-IPTA application used factor 2 in range and
1.5 in azimuth.
For IPTA - factor 2 in both directions.What will be the result for processing, if used slc_ovr with factor 2 in range
and azimuth, and then used even factor for multi-looking (2, 4 etc.)? Or main
reason consist of used odd multi-look factors (3, 5...)?Thanks!
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oversampling and multi-looking - Added by Charles Werner about 1 month ago
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Hi,
First of all, which program? I think the documentation describes what happens.
Generally, if the multi-looking factors are even, then the data are oversampled
by a factor of 2 first to permit symmetrical weighting.
and then downsampled. That is why windows with odd width and height values
require less processing.
Best regards,
Charles
On 01.07.2025 11:09, Igor Babayants wrote:
GAMMA Questions - SAR Data Preprocessing: oversampling and multi-looking
<https://dep1doc.gfz.de/boards/19/topics/663>/Igor Babayants/
Hello!
slc_ovr: you recommended for non-IPTA application used factor 2 in range and
1.5 in azimuth.
For IPTA - factor 2 in both directions.What will be the result for processing, if used slc_ovr with factor 2 in range
and azimuth, and then used even factor for multi-looking (2, 4 etc.)? Or main
reason consist of used odd multi-look factors (3, 5...)?Thanks!
You have received this notification because you have either subscribed to it,
or are involved in it.
To change your notification preferences, please click here:
http://dep1doc.gfz-potsdam.de <http://dep1doc.gfz-potsdam.de>