<< Click to Display Table of Contents >> Navigation:  Help Content > General Tools > Orbital Correction > Update to Precise Orbits > General Tools - Orbital Refinement - Update to Precise Orbits - Precise/Preliminary Orbits

Purpose

 

Standard orbits, which are provided with ERS-1/2 products, can be updated using precise (PRC) or preliminary (PRL) ones.

 

Technical Note

 

Precise and preliminary orbits, which are made available through the DLR ftp server, can be used to update the relevant information in the data header file. This procedure is especially useful for interferometric processing purposes, where an improvement of just 1 meter or less - in terms orbital parameters accuracy - can dramatically improve the quality of the final processing results.

 

Access to these data can be required to the ESA Earth Observation Help Desk. The zipped orbital data are stored, in the "orbprc" or "orbprl" folder, within directories named according to the satellite name (i.e. ERS1 or ERS2) and acquisition year.

 

The zip file nomenclature contains information relevant to both acquisition period and absolute orbit number (i.e. validity time begin), which enable to identify the file to download. The orbit file to use must be the closest, but previous (in terms of date/orbit), with respect to the input satellite acquisition date/orbit.

 

Input Files

 

Input Orbit File

Unzipped orbital data. This file is mandatory in case do repository directory is set in the SARscape preferences.

 

File to Update

Input file name of the SAR data (e.g. _slc) to update. This file is mandatory. The data must have been previously imported.

 

Output Files

 

_OLD...        

Copy of the header files (.sml, .hdr) containing the old - not updated - orbital parameters.

 

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

 

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.