The CORS Stations tab displays details about relevant NGS CORS Stations to be used for processing.  For more information on NGS CORS please reference this link. 


If a message box with "No stations found within 0 km." pops up before retrieving data then return to the File>Settings dialog and verify the parameters.





Locator is designed to retrieve the necessary CORS data that will overlap the collection times and download these files to your project folders.  As NGS deprecates data over time, it is recommended to download within two days of collection and retain the data until your project is complete. Don't worry if data is not downloaded within two days, valid processing can be completed using any of the downloaded correction data.


The GNSS data collected at CORS stations are available within approximately one (1) hour (60 minutes) from when they were recorded at the remote site.  A few sites have a delay of 24 hours (1440 minutes).


  • Hourly files are only kept for two days.
  • Daily files are kept permanently.


However, after 30 days, daily files are decimated to 30-sec sampling rate and after six months, only compressed files of daily data are provided.  InTerra does not commit to retrieving data after six months.


All data that is downloaded with the project is stored locally and will be usable as long as the project is retained.




Locator will display the Name, Distance (km), Agency maintaining the unit, and the downloaded file path.  To the left side of the grid is a check box to use the currently selected CORS data.  Often times one unit is sufficient to attain desired results, especially with relatively close CORS units.  The more units selected the longer processing will take as the matrix math is scaling up.  A click to turn off the "Use" will remove the unit from computation, but the files are retained.


Now all data is loaded and selected for processing, clicking the Results tab will start processing.  This step will take considerable computing power and several minutes to complete, please enjoy a cup of coffee while you wait.