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Purpose

 

This functionality defines the SAR pair combination (Reference and Secondarys) and connection network, which is used for the generation of the multiple differential interferograms. This step is mandatory. Unlike the SBAS tool, this network cannot be edited.

 

Technical Note

 

The network links created in this step are only those connecting pairs that are within the spatial baseline values specified in the relevant "Preferences", (refer to the Preferences>Persistent Scatterers>Baseline Threshold (%) setting). Those acquisitions which remain disconnected, due to baseline values exceeding the specified thresholds, are discarded from the further PS analysis.

 

At the end of the processing a graph is shown, where all connection are represented as well as the selected Reference. Each acquisition is represented by a diamond associated to an ID number, which is reported also in both the "CG_report.txt" file. The colour of the diamond symbol is as follows: i) Discarded acquisitions due to user specific constraints in red colour; ii) Valid acquisitions in green colour; iii)  Reference acquisition in yellow colour.

 

The following graphs are generated:

 

•Time-Position plot, which provides the normal distance from the Reference (y axis) and the input acquisition dates (x axis).

•Time-Baseline plot, which provides the normal baseline (y axis) and the input acquisition dates (x axis).

 

They can be reloaded at any processing step by means of the relevant tool.

 

The multilooking factors of the output Reference image (suffix, "_pwr") are automatically calculated by taking into account the Cartographic Grid Size, which is set in the relevant SARscape Preferences panel.

 

Auxiliary file        

It contains information to understand which steps have been executed and what are the products generated.

 

 

Input Files

 

Input file list

Input files (_slc, _slc_list) to be used. This file list is mandatory.

 

Optional Files

 

Input Reference file

Name of the the acquisition to use as processing reference data. This acquisition must be contained in the "Input File list" as well. If this file is not entered the program identify it in order to have the maximum number of connected acquisitions. This file is optional.

 

Output Files

 

Output Root Name

Name of the output root. This file is mandatory. It is used as root name throughout the entire PS processing chain.

 

connection_graph

Directory containing the following products:

•Multilooked Reference intensity image (_pwr) and associated header files (.sml, .hdr).

•Report file (Reference_selection.txt) showing various input selection parameters such as: selected Reference, baseline and precision values, and thresholds, etc.

•The "plot" sub folder is used to store the files (CG_baseline.txt and CG_position.txt) used for the visualization of the graphs and interfacing with ENVI.

•CG_report.txt file showing the input file list, that is automatically updated once the Edit Connection Graph tool is performed.

 

Details specific to the Units of Measure and Nomenclature of the output products can be found in the Data Format section.

 

auxiliary.sml

Text file with process related information (products, parameters, etc.)

 

General Functions

 

Exec

The processing step is executed.

 

Store Batch        

The processing step is stored in the batch list. The Batch Browser button allows to load the batch processing list.

 

Close        

The window will be closed.

 

Help

Specific help document section.

 

 

Specific Function(s)

 

None.        

 

See Also

 

Task, SARscapeBatch object, SARscapeBatch script example

 

References

 

None.