A Maritime GNSS Based Integrity Concept for Port Approaches

Kurzfassung

Global Navigation Satellite Systems (GNSS) are the most important source of deriving a Position, Navigation and Timing (PNT) solution. With the increasing use of driver assistance functions and potentially autonomous vehicles it is not only of upmost importance that the PNT solution is accurate but also reliable. For this, GNSS integrity concepts based on specific applications and ship operations are essential to ensure a continuous, reliable navigation solution. This work presents a maritme integrity concept created in the ESA activity TEGMAR which combines routes with safety margins derived from historical Automatic Identification System (AIS) data with classic GNSS integrity algorithms to enable safe port approaches. This allows for continuously checking the adaptive alert limits from the route against the current protection level from the navigation solution. The presented concept will be evaluated on real measurement data from a ferry vessel as well as Spirent simulations based on port entries this vessel. This enables injecting GNSS and Inertial Measurement Unit (IMU) feared events into the simulations to check whether an approach is feasible under hazardous conditions and what the impact on the navigation solution would be. The integrated PNT solution including the different alert and protection limits are displayed in a Graphical User Interface (GUI) as part of a MATLAB framework for this digital testbed. Disclaimer: The view expressed in this publication can in no way be taken to reflect the official opinion of the European Space Agency.