University of Tehran Launches Indigenous GNSS Software, Advancing Geomatics Self-Sufficiency
The Satellite Geodesy Laboratory of the Faculty of Surveying Engineering and Geospatial Information at the College of Engineering, University of Tehran, has successfully developed indigenous software for sending real-time corrections for precise satellite positioning and online processing of GNSS observations.
According to the University of Tehran's public relations office, this software has been completely designed and developed at the University of Tehran with the aim of fully replacing imported software and reducing dependence on foreign technologies. It has been tested and evaluated on the network of permanent stations of the National Iranian South Oilfields Company.
The presented software is a modern, secure, and intelligent platform for processing observations from global positioning satellites including GPS, Galileo, BeiDou, and GLONASS. This system has the capability to automatically and precisely process observations using static, PPK, PPP, and SPP methods, as well as quality control of observations, and enables the implementation of various positioning methods and real-time monitoring of ionospheric and tropospheric effects.
This software, with support for various types of GNSS satellite data, is considered a practical tool for surveying engineers, researchers, companies, and organizations active in the field of satellite data measurement and monitoring. The designed system has various capabilities including connection to reference stations and receiving corrections in both client and server modes, support for all existing GNSS constellations and signals with the ability to update them in the future, simultaneous support for at least 50 permanent GNSS stations and 200 users, and phase ambiguity resolution for baselines up to 70 kilometers.
Providing 2 centimeter horizontal and 3 centimeter vertical relative accuracy in static mode with a maximum 15-minute occupation time, 4 centimeter horizontal and 5 centimeter vertical relative accuracy in PPK and NRTK methods, and providing corrections with a maximum permissible delay of 0.5 seconds are among the other technical features of this system.
This software also has the capability to connect to reference stations through serial ports, TCP and UDP, support for NTRIP protocol versions 1 and 2, display of online maps with a background similar to Google Maps, and the ability to view the position, status and information of CORS stations and active users, and generate KML output.
Support for various data formats including RTCM2.x, RTCM3.x, RINEX 2.x, RINEX 3.x and raw data, information archiving, no limitation on the number of RTCM inputs, modeling of corrections and sending them using NEAREST and VRS algorithms, and the ability to analyze and quality control data along with graphical display and generation of specialized reports are among other features of this system.
Among the advanced capabilities of this software are modeling error behavior in state space (State Space Representation) and observation space (Observation Space Representation), logging and viewing logs of all system events, user and station activities, post-processing of raw data in differential mode in Static and Stop and Go modes, point processing of data in SPP and PPP modes, and analysis of behavioral models of ionospheric and tropospheric effects by extracting STEC and ZTD parameters.
Also, the ability to monitor the coordinates of reference stations in real-time, record and display the history of their changes, and benefit from an advanced service portal with various access levels for users, has made this software a comprehensive indigenous system in the field of precise satellite positioning.
The Satellite Geodesy Laboratory of the Faculty of Surveying Engineering and Geospatial Information at the College of Engineering, University of Tehran is managed under the supervision of Dr. Saeed Farzaneh, a faculty member of the University of Tehran, with the participation of various students and researchers.
