Orbit determination

GNSS applications

Aerospace engineering

GLONASS

Geodesy

Engineering

Satellite

Geography

Galileo (satellite navigation)

Orbit (dynamics)

Ambiguity resolution

Computer science

Global Positioning System

Spacecraft

Remote sensing

Telecommunications

Advances in Space Research

We present an update on the multi-GNSS orbit and clock solution (COM), the CODE analysis center provides to the International GNSS service (IGS) in the frame of the multi-GNSS extension (MGEX). In recent years substantial progress was achieved in the fields of orbit modelling (Earth albedo, transmit antenna thrust, thermal radiation, eclipse attitude law), receiver and transmitter antenna calibration, ground tracking network, data dissemination, completeness of satellite constellations, availability of spacecraft-related meta information, observation biases, and ambiguity resolution. This led to improvements in orbit and clock parameter estimation, which are substantial for the European GNSS Galileo and are to a large part attributed to the availability of disclosed spacecraft meta data. Orbit and clock validation of the COM results using different validation methods (SLR residuals, orbit misclosures, linear fit of clock corrections) indicate that the quality of the updated Galileo products is meanwhile on the same level as for corresponding GPS and GLONASS products. Based on these achievements CODE decided to include Galileo in its IGS Rapid and Ultra-Rapid products and to contribute to the third reprocessing effort of the IGS with a three-system solution including GPS, GLONASS, and Galileo.

Overview of CODE’s MGEX solution with the focus on Galileo