InU : Unwrapped Interferogram

Product Description

The product corresponds to the unwrapped interferogram.

The geotiff file has 2 bands:

  • band 1 is the filtered unwrapped phase of the interferogram. By default, the filter is a moving averaged, triangular sliding window applied on the wrapped phase (see Doin et al., 2015, for example). By default, unwrapping is done by the method described in Grandin et al., 2012.

  • band 2 is by default the coherence obtained when the sliding window average has been applied on the wrapped interferogram: it thus quantifies the quality of the filtered phase. It can also be the product of the two image’s amplitudes if other types of filters have been employed.

The png file has 1 band:

  • band 1 is the unwrapped phase difference of the interferogram, normalized by a color palette

Available products

The InU produts are available in one resolution:

  • runw= 8 or 16 (resolution of unwrapped interferogram)

The final Unwrapped Differential Interferogram are computed in two geometries (radar: InU_radar or ground geometry: InU_geo ):

Processing Details

The Unwrapped Interferogram has been filtered (see filtering parameters in metadata). Possible corrections have been applied before unwrapping including ramp (in range or in azimuth) and atmospheric corrections. They are described in metadata. In the metadata file, the following parameters report the unwrapping options:

  • unw_method (unwrapping method used)

  • threshold_unw (minimum threshold: pixels that have a band 2-value above this thershold will be unwrapped)

  • atmo (atmopheric correction used)

  • ECMWF_model (atmopheric model used)

  • do_wrapped_ramp (estimate a ramp in range)

  • nfit_range (degree of the ramp)

  • thresh_amp_range (threshold on the amplitude for the ramp in range correction)

  • do_wrapped_ramp_az (estimate a ramp in azimuth)

  • nfit_az (degree of the ramp)

  • thresh_amp_az (threshold on the amplitude for the ramp in azimuth correction)

  • do_corr_dem (DEM correction)