Gamma DIFF&GEO: Reference Manual

S1_deramp_TOPS_reference

C-shell script: S1_deramp_TOPS_reference

NAME
S1_deramp_TOPS_reference - Script to deramp a Sentinel-1 TOPS mode burst SLC reference.

SYNOPSIS
S1_deramp_TOPS_reference <SLC_tab>

<SLC_tab>

(input) 3 column list of TOPS burst SLC reference (SLC, SLC_par, TOPS_par; row order IW1, IW2, IW3)

EXAMPLE
S1_deramp_TOPS_reference 20141003.SLC_tab

Conducts a deramping of the reference burst SLC data. The filenames for the deramped data and the phase ramp are generated based on SLC_tab.

DESCRIPTION
S1_deramp_TOPS_reference is used to deramp the burst SLC data of a S1 TOPS reference scene. For each burst the azimuth phase ramp caused by the Doppler Centroid variation is calculated and subtracted. Both the deramped data (as burst SLC, i.e. with the individual files for each sub-swath) and the phase ramps subtracted (in the same format, but using float values) are generated.

The filenames for the output files are automatically generated based on the filenames of the input data. The output SLC_tab for the deramped burst SLC consists of the SLC_tab name with ".deramp". Similarly, the burst SLC file names of the deramped data are generated:
20141003.RSLC_tab --> 20141003.RSLC_tab.deramp
20141003.IW1.rslc --> 20141003.IW1.rslc.deramp
20141003.IW1.rslc.par --> 20141003.IW1.rslc.deramp.par
20141003.IW1.rslc.TOPS_par --> 20141003.IW1.rslc.deramp.TOPS_par
The corresponding file names for the deramp phases subtracted are:
20141003.IW1.rslc.deramp.dph, 20141003.IW2.rslc.deramp.dph, and 20141003.IW3.rslc.deramp.dph.

The azimuth spectra of the deramped data should be in the base band and centered and should not vary in azimuth direction. To check the spectra you can use the program dismph_fft.

Deramping of the S1 TOPS data may be used to apply oversampling in offset tracking, apply common band filtering in azimuth direction or to apply split-beam interferometry, or to use the spectral diversity criteria in the IPTA for the point target candidate identification (program sp_stat). For differential interferoemtry, on the other hand, deramping of the S1 IWS data is not necessary.

OPTIONS
To deramp a co-registered slave burst SLC with the same phase ramps as used to deramp the reference burst SLC the program S1_deramp_TOPS_slave.html can be used.

To generate an SLC mosaic of the deramped burst SLC reference the ISP program SLC_mosaic_S1_TOPS is used.