RTX-PP Engine

The RTX-PP Engine is a post processing tool that uses the Trimble RTXÔ Post-Processing service to calculate highest-precision coordinates using locally stored observation data. The module takes observation files (in a specified file format, such as RINEX v2.xx and higher, Compact RINEX, DAT, TGD, T01 or T02) and sends them to the Trimble RTXÔ Post-Processing service, where absolute positions using precise orbits are calculated using the raw observation data. These absolute positions as well as the number of usable epochs are then returned to the RTX-PP Engine, where they are compared to the known reference coordinates of the respective station.

The processing results are passed on to dependent modules for filtering, adjustment, and data display. The RTX-PP Engine works in static mode.

Connecting to the server

For being able to use the RTX-PP Engine, the computer on which the module is hosted must support TCP/IP connections to the Internet. When a session is started, the RTX-PP Engine automatically connects to the RTXÔ Post-Processing service using a secure connection (SSL standard). It is not necessary to specify the connection or an authentication key - this information has already been stored internally when Trimble 4D Control Server has been installed. The RTX-PP Engine disconnects from the server as soon as it has received the required information.

Adding the module

The RTX-PP Engine module is available from the Tree view root Trimble 4D Control Server. Trimble 4D Control Server accepts multiple RTX-PP Engine modules in the system.

When the module is being added, the RTX-PP Engine Properties dialog appears. It lets you define and select module configurations. Each configuration holds information on the processing mode, the data sources, the time segment to be processed, outlier filtering, and processing parameters. You may remove a configuration from here, if you do not need it anymore. You may change the settings of the selected RTX-PP Engine configuration at any time.

Network definition

Set up the network for post processing using the list of reference stations defined in the system. There is no necessity for the stations to currently be added to the Device Manager module.

If the RTX-PP Engine cannot find session data of the specified period for a selected station, the station cannot be part of the session and will not be processed.

Processing

The RTX-PP Engine scans a specified folder and its subfolders for observation files (including zipped files) of a specified period and creates a set of stations from the available data. This scan is repeated in specified time intervals. During runtime, the module connects to the RTXÔ Post-Processing service, uploads the observation data files and receives the current positions from the observations for all stations in highest precision. The module then compares the current positions to the known positions. Each session results in one position per station.

The RTX-PP Engine calculates for each station the position offsets from the reference coordinates (DN, DE, Dh, and D3D). Of course, the processor respects antenna height offsets. If the known positions of the stations are periodically updated to the current epoch due to known velocities, the processing re-starts with the new positions.

Stopping and continuing the process

Use the module's shortcut menu to stop and continue the post processing.

Output of results

The results of the folder scanning and the results of the last and previous estimation processes are displayed in numerical form at the RTX-PP Engine views. In combination with the Integrity Monitor and the Alarm Manager modules, alarms can be triggered and issued if displacements or errors exceed specified thresholds.

The RTX-PP Engine stores the results of its estimation process to the database. Thus, they are available to depending Integrity Monitor modules. From the Integrity Monitor module, external devices can request positions for selected stations and receive them as NMEA strings. The RTX-PP Engine stores one epoch per session to the database.

Note - Use the Integrity Monitor module to display the offsets between the known coordinates of a station and its estimated position (displacements) in numerical and graphical form. Using the Integrity Monitor module you can also hold different or additional stations fixed and thus perform an adjustment on the estimated positions of the unfixed stations. In this case, the resulting positions and maps refer to the adjusted coordinates.

Logging into the database

The RTX-PP Engine module writes for all stations the positions of accepted solutions into the central database. The database contains the following tables referring to the RTX-PP Engine system:

Table name	Contents	More information
MeanPos_PPxEngine_<config name>	Position vector and covariance matrix components; fixing status, coordinate type, DOP, and number of GPS/GLN satellites.	One row for each station. *
PPxEngine_<config name>	Session and event times ; position vector and covariance matrix components; coordinate type, DOP, and number of GPS/GLN satellites.	One row for each session and each station. Session time is the last epoch of processed period.

Table name

Contents

More information

MeanPos_PPxEngine_<config name>

Position vector and covariance matrix components; fixing status, coordinate type, DOP, and number of GPS/GLN satellites.

One row for each station. *

PPxEngine_<config name>

Session and event times ; position vector and covariance matrix components; coordinate type, DOP, and number of GPS/GLN satellites.

One row for each session and each station.

Session time is the last epoch of processed period.

*By default, the data of these tables is reduced depending on settings of the TableLifeTime table.