Ships of all sizes converge on areas surrounding coastal ports and access to waterways. In managing marine traffic in these congested areas, authorities have implemented traffic routeing, ship reporting and vessel traffic services (VTS).
A vessel traffic service is a marine monitoring system used to keep track of vessel movements and provide navigational safety in a limited geographical area. Within the EU, Member State authorities are also required to ensure vessels use routing, reporting and VTS in compliance with the regulations in force. European regulations also require the use of an Automatic Identification System (AIS) when in these areas.
Authorities use the AIS data for their traffic information systems. The data is used to compile a traffic “image” which provides information about all vessels, including their intentions and the factors influencing their movement. The information is part of the decision making process of managing marine traffic to anchorage and from anchorage, or for transit inward, to port or outward to sea.
In these areas, vessels navigate in very close proximity to each other. Some of these vessels will also have dimensions (height, width, length or depth) that restrict them to deep-water routes and make them dependent on local tides, river flows and meteorological conditions. By its nature vessel management in such areas is safety critical.
GNSS is used for position information by AIS and for ship navigation. Terrestrial or space-based services might be used to augment the GNSS positioning.
The EGNOS solution
EGNOS provides high integrity and accuracy. These are two very important components that benefit the management of vessels, the advice given for speed and course and the navigation of vessels within a VTS.
EGNOS provides within Europe, and as a component of global satellite-based augmentation systems (SBAS), the means of ensuring that all vessel in vicinity of VTS or within ship routing systems have a high standard of navigation information to use for safety critical applications. EGNOS can provide robust decision support in all states of weather and visibility.
By also equalising the accuracy of navigation in an area, EGNOS-supported VTS will be able to use the relative velocity of each vessel within a decision support process to allow incremental alterations of velocity, rather than periodic larger changes.
The benefits of using EGNOS in such a way are a more efficient use of waterways, reduced fuel consumption through the smoothing of velocity changes, improved safety, better ship and traffic performance, and a resulting reduced impact on the environment.
Lastly, more robust VTS and planning tools will have a marked positive impact on the efficiency of a number of port processes that can benefit from quicker turnarounds and better scheduling.