Mathematical Approaches in GNSS Positioning and Integrity Monitoring

The development of Global Navigation Satellite System (GNSS) augmentation systems plays an important role for the warranty of high accuracy and integrity in satellite based positioning. Since 2006 the DLR has developed an experimental “Maritime Ground Based Augmentation System (MGBAS)” for safety critical maritime applications (e.g. port and docking manoeuvres) in the research port Rostock. On the one hand, this system allows the users to mitigate typical GNSS errors, like atmospheric delay, by the provision of Real-Time Kinematic (RTK) services. On the other hand, it supports the detection of faulty satellite signals and the assessment of the possible positioning accuracy aboard. At the beginning, this talk will outline the least squares based principle of satellite positioning. Afterwards the currently implemented RTK algorithm based on Kalman-Filter and Integer Least Squares (ILS) will be described. Concluding, a brief introduction to issues of integrity monitoring will be presented