A pseudolite position solution within a Galileo test environment for automated vehicle applications

Automated vehicle applications have a high automation potential in terms of safety and efficiency improvement. Autonomous or semi-autonomous navigation requires a positioning solution of high accuracy and robustness. By introducing the new European Galileo satellite system, multi-constellation with GPS offers new opportunities of accuracy and integrity enhancements. Although, the Galileo system is still in buildup phase, Galileo test environments (GATEs) allow testing Galileo applications. The present publication shows the extension of an existing GNSS-aided sensor integration filter, enabling the GATE applicability. Focus is put on the particular localization conditions in terms of geometrical constellation of ranging sources. A GNSS-only snapshot algorithm is considered making use of a 2D approach. Extensive sensitivity analysis shows robustness of this approach, even with a minimum set of available ranging sources of unfavourable geometrical constellation. Afterwards this 2D approach is carried towards the tightly-coupled filtering of GNSS observables and Inertial Measurement Unit (IMU). Testing and Validation is performed at automotiveGATE, which is part of an automotive test track near Aachen. Even without any pseudo-range corrections the results of the filter algorithm show 2D average positioning errors less than 0.7 m in areas of geometrical constellation with acceptable horizontal and high vertical Dilution of Precision (DOP).