Differential GNSS and PPP

Differential GNSS

Differential processing can be selected if base station(s) have been added to the project. This method of processing provides access to ARTK, where carrier phase ambiguities are fixed for high accuracy applications.

PPP

PPP is an autonomous positioning method where data from only one receiver is used. If base station data has been added to the project, it will not be used when processing PPP. By design, both differential and PPP trajectories can be processed within the same project without overwriting each other.

The PPP processor requires dual frequency data, but can be processed with or without precise orbit and clock files. The software will attempt to download precise orbit and clock files if the option to “Allow processing without precise files” is disabled and if the Process button clicked prior to adding precise data to the project.

Figure 24

TIP: To check the validity of GNSS data with reasonable certainty immediately after a survey, a user could process the PPP solution “allowing processing without precise files”.  Enabling this option makes use of the broadcast ephemeris data acquired during data acquisition, rather than referencing a [service] base station or waiting for precise files to be uploaded on public servers.