How to Load GNSS Observations into OPUS
=======================================

OPUS should be capable of ingesting the most common vendor-specific GNSS file formats. If the file format is not recognized, OPUS will show a file upload error. In that case, refer to your vendor for tools to convert your proprietary file format to the Receiver Independent EXchange format (RINEX).

The information required for successful uploading to your project includes:
 
* GNSS observation file name (either RINEX file or other file format supported by OPUS: see `here`_ for more information on data files supported)

.. _`here`:  https://geodesy.noaa.gov/OPUS/about.jsp#rinex_file

* Antenna type and model (to apply the correct antenna phase center offset; see NGS `Antenna Calibration`_ for more information)

.. _`Antenna Calibration`:  https://geodesy.noaa.gov/ANTCAL/index.xhtml

* Antenna height (meters) -this is the vertical distance from the vertical point of reference of the usermark to the GNSS Antenna Reference Point (ARP).

.. caution::

  OP will retain antenna heights to the fourth decimal place (0.0001 m) in its computations, but will only display antenna heights rounded to the nearest millimeter in output files and tables (0.001 m) 

* Email address

To add the observation to your project, the user must click on the "Options" button and submit the project identifier that was assigned to the project upon its creation:

.. _Figure6-2.jpg:
.. figure:: ../images/Figure6-2.jpg
   :width: 600 px
   :alt: Project Identifier Option

   Project Identifier Option

.. caution::

  If the user's profile is used, be careful that the correct antenna model and antenna height are selected. Using the profile can be a powerful tool, but it can also lead to unintended consequences if the user is not careful. 

.. tip::

  Delete My Profile before each new project is populated with observation data to make sure unintended errors are not introduced when data are uploaded into a new project

**ZIPPING FILES**: If all of your antennas are the same type and model (i.e. they all have the exact same antenna center offset per the antenna calibration) and were all set at the same height, you can bulk upload the observation files after first zipping them into one \*.zip file, and pointing to the zipped file at the time of upload.

-------

.. toctree::
  :maxdepth: 2