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GMTSAR
http://topex.ucsd.edu/gmtsar
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[Help]: Question about the effect of filter_wavelength, range_dec, and azimuth_dec in batch_tops.config on final results of S1 InSAR #913

Open ATDehkordi opened 5 months ago

ATDehkordi commented 5 months ago

Hi everyone,

If we consider using an S1 time series with a spatial resolution of 5x20, what are the effects of filter_wavelength, range_dec, and azimuth_dec in batch_tops.config on the final results? If range_dec and azimuth_dec are set to their default values of 8 and 2, respectively, will we get a final velocity map with a resolution of 40x40 (resulting from multiplying 8x5 and 2x20)?

Does filter_wavelength also affect the spatial resolution?

Regards

Xiaohua-Eric-Xu commented 4 months ago

If you don't set range_dec and azimuth_dec, the decimation will be set to ~8 samples per wavelength in radar coordinates and ~4 samples per wavelength after geocoding.

As for your description, the sampling space is as your description. Yet sampling is different from resolution, in the sense that if you filter the data at, e.g., 400m, it would not make sense to sample every 5m.