NAVWAT will examine the requirements and the related requirements evolution of future GNSS for high precision
applications in inland waterway navigation. For the purpose of this project, three application scenarios have
been identified, all having a high demand for accurate and reliable position information.
In inland navigation the only certified navigation tool is radar which is in an ideal case combined with the
information from ENC (Electronic Navigational Chart) where the radar image is overlaid onto the digital chart
(radar overlay). The accuracy in such case is in the range of meters, limited by the accuracy of radar. Additionally,
this system does not take into account the shape of the vessels or convoys and hence the provided information
does not provide accurate distance information to the surrounding infrastructure. The utilisation of such a
system for the approach or passing of riverside infrastructure is hence not possible. At present, in such situations,
visual navigation is the only feasible option.
Figure 1: Cargo vessels (Source: via donau, F. Dosch)
Within NAVWAT the requirements for future GNSS will be evaluated based on the requirements evaluated for three
representative applications form the inland waterway domain. These applications require high precision navigation
information and deal with the following navigation situations:
- Approach of a vessel to a river lock
- Approach of a vessel to a bridge
- Approach of a vessel to ports and river-side berths.
Figure 2: Approach to river lock (left) and approach to berth (right)
The NAVWAT application utilises modern GNSS and augmentation infrastructure to provide accurate position information.
This precise position information will then be related to the information contained in the onboard ENC. The
system will take into account the actual shape of the vessel or convoy and will relate the information provided
to this vessel shape and not only to the GNSS antenna position. The aim is to provide the distance from the vessel
hull (represented by characteristic points) to close riverside infrastructure on a real time basis. This should
provide the shipmaster with the information needed to ensure a safe passage through these difficult navigation situations.
Thus, a system concept will be developed which supports the shipmaster in such situations, in particular under
limited visibility (e.g. dense fog, heavy rainfall, etc.). From the present point of view, an integration or
combination with the already used ship-side technology ECDIS (Electronic Chart Display and Information System)
seems to be the most suitable solution for visualisation of the information.
The technical description of the application focuses on general application related and technological features.
The minimum performance expected from the user terminal is also described in detail. A feasibility assessment
considering the 2015 timeframe (and beyond) and takes a look at new features of future GNSS.
The analysis of the requirements for future GNSS systems first includes an assessment of the drawbacks of the
current GNSS generation. This is followed by an analysis of possible future GNSS-based technologies which could
fulfil the application requirements. The technical description is closed by the minimum performance expected for
the evolution of GNSS.
The third part of the project deals with an assessment of the current GNSS generation under development. This
includes next to modernised GPS and GLONASS, Galileo and EGNOS also the Chinese system COMPASS. The performances
of the individual systems as well as combinations of these systems are then mapped with the draft user requirements
identified for the timeframe up to the year 2015 (and also 2025).