AIRSAR Along-Track Interferometry Experimental Datasets
The files associated with each ATI interferometric pair are located in separate folders. The naming convention is:
{frequency band}{Transmit Antenna}{Receive Channel}
I.e., ‘caf’ means: transmit at c-band from the aft antenna and receive with the forward antenna. The interferogram is denoted by a pair of these. For example, ‘caf_caa’ means the product of the ‘caf’ channel with the (complex conjugate of the) ‘caa’ channel. The interferometric pairs provided in this experimental dataset are:
caf_caa C-band half baseline:
cff_caa C-band full baseline
caf_cfa C-band one-pulse baseline
laf_laa L-band half baseline
lff_laa L-band full baseline
laf_lfa L-band one-pulse baseline
Within each of these folders are the following files comprising the ATI data set for a given interferometric pair:
File Name File Format Description
*ppp ascii Log File
*par ascii Parameter Summary File
*azNxM r*4 Magnitude image, slant range, N range& M azimuth looks
*intfNxM c*8 Slant-range interferogram (single look)
*ccNxM c*4 Slant-range correlation map
*intf-grid r*4 interleaved Ground range wrapped velocity map and magnitude image
*inc.map r*4 Ground range incidence angle map
Log File
The log file is a text file generated during data processing and is a complete record of the data processing steps and parameters.
Parameter Summary File
Text file that summarizes key data parameters culled from the Log File. This should be more readable than the log file, and should contain the most critical information for viewing the data files of interest. Note especially the caveats at the end of the parameter file.
Imagery Files
Multi-looked slant range image data are included. These are magnitude-only images. There is no radiometric calibration in these data or in any of the other ATI datasets.
Slant Range Interferograms
These are provided for each baseline and are complex samples where each corresponds to the result of the complex multiplication <v1v2*>, where v1 and v2 are the complex samples for each interferometric channel. There is an un-calibrated global phase offset for each interferogram.
Slant Range Correlation Maps
Slant range correlation information:
Ground Range Velocity Maps
Interleaved lines of mag(v1v2*) and the unwrapped velocity. Note that the magnitude in these files is not the same as the correlation – it is an "un-normalized" correlation.
Ground Range Incidence Angle Map
The incidence angle of the radar illumiation at any sample, corresponding to the ground range velocity map. There is an uncalibrated global velocity offset for each map.