The VHF Data Exchange System (VDES) is a system under development designed to contribute to e-navigation and digitisation of shipping. In 2015, Space Norway, in partnership with Kongsberg Seatex and FFI, won a contract for the development of a prototype VDES payload. Since then, the company has established a leading role internationally in specification, development and testing of the VDES system. The focus has been on the system’s satellite component. With the advantages of the VDES system, there is reason to expect that the system will become an important communication platform for global shipping and an important contribution to increased safety and digitisation of shipping.

The Automatic Identification System (AIS) was introduced by the UN’s maritime organisation IMO1 to enhance safety at sea. AIS sends information about position, course, velocity and the ship’s identity using VHF radio signals. All ships over 300 gross tons are required to use AIS. The system is mainly an anti-collision system that provides information directly to each ship about nearby traffic as well as warnings of risks for collision or close passage. The system also provides a detailed real-time picture of ship traffic within a region and is utilised by the Norwegian Coastal Administration for monitoring traffic in its areas of responsibility. However, the ground level range of the system is limited to the receiving station's visibility above the horizon. For an AIS base station on land, this usually means a maximum range of approximately 70-100 kilometres. Areas further from coastal stations, such as open oceans and Arctic waters, are therefore beyond reach of land based AIS base stations. This represents a challenge for the Norwegian authorities’ ability to monitor traffic in our waters.
In 2005, the Board of the Norwegian Space Agency invited Norwegian companies to propose satellite-based AIS-solutions, where a project proposal from the Norwegian Defence Research Establishment (FFI) for an AIS receiver in space won the competition. AISSat-1, Norway’s first national surveillance satellite, was developed in a partnership between FFI, the Norwegian Coastal Administration, the Norwegian Space Agency and Kongsberg Seatex. The satellite was launched in 2010, proving that satellite reception of AIS signals using small and cost-effective micro-satellites was feasible. According to Arve Dimmen, director of maritime safety at the Norwegian Coastal Administration in 2010, it was like turning on the lights at sea - they could now “see” ships across vast ocean regions. With AISSat-1, Norway became one of the first nations in the world to operationalise satellite-based reception of AIS signals. The Norwegian Coastal Administration currently owns five AIS satellites. Space Norway subsidiary Statsat is responsible for the operation of the satellites, and Kongsberg Seatex supplies the technology for signal reception.
The VHF Data Exchange System (VDES) is a system under development designed to contribute to e-navigation (digitisation of shipping). IMO and IALA2 have been the driving force behind this technology. VDES will enable two-way, low-speed communications with ships around the world, including the Arctic region. VDES can be seen as the next generation AIS and operates within the same frequency range. The system specification for VDES was adapted for use via satellite, as a result of an initiative by ESA in 2014. A major advantage is that there is no need for new antennas on board ships or on land as the system uses existing VHF antennas. By supplementing coverage from landbased stations with coverage from satellites, VDES will in the future provide a seamless, global system for low-speed communication to/ from ships.

In 2015, Space Norway, in partnership with Kongsberg Seatex and FFI, won a contract for the development of a prototype VDES payload, which has been demonstrated on vessels in the Arctic oceans. The company has established a leading role internationally in specification, development and testing of the satellite-based VDES system. Communication via satellites requires access to suitable frequency bands, which is a limited resource. Allocation and coordination of frequencies is managed through the International Telecommunications Union (ITU), a UN organisation where member countries participate and influence how, and for what use, frequencies are allocated. Allocation and coordination of frequencies is a complex process where a number of different interests are taken into account.
Space Norway has made a significant effort in international bodies such as CEPT3, ITU and IALA in the preparatory work leading up to the allocation of frequencies and standardisation of the VDES system. Lars Løge from Space Norway acted as coordinator for Europe (CEPT) on the issue of frequency allocation for VDES both in preparation for and during the World Radiocommunications Conference in 2019 (WRC-19). Norway – through a partnership between Space Norway and the Norwegian Communications Authority – was instrumental in achieving frequency allocation for VDES at WRC-19. This would not have been possible without comprehensive efforts in the form of system development, measurements and testing of VDES signals on NorSat-2, supported by ESA, the Norwegian Space Agency, the Norwegian Coastal Administration and the Norwegian Maritime Authority.
Examples of VDES-based services are:
- Satellite-based retransmission of AIS messages for increased situational awareness and navigation in the Arctic.
- Broadcasting of ice maps to ships.
- Distribution of search patterns in connection with rescue operations at sea.
- Ship reporting, also in partnership with EMSA (European Maritime Safety Agency).
- Broadcasting of EGNOS correction data and next generation GPS and Galileo integrity messages for better and safer positioning.
- Precise time and position via VDES.
Space Norway works closely with our partners at Kongsberg Seatex, EMSA and the Norwegian Coastal Administration, with support from the Norwegian Space Agency and ESA in making VDES an operational capacity. Norway is a world leader in this area and the only nation that currently has an operational VDES satellite in orbit. Space Norway has recently acquired an updated and more capable VDES payload from Kongsberg Seatex, which will be one of the payloads on the Norwegian Space Agency’s satellite NorSat-TD, planned for launch in 2022.
The collaboration with the industry has been close and productive, and Kongsberg Seatex is positioned as a leading international supplier of both ship equipment and satellite payloads for VDES. With the advantages of the VDES system, there is reason to expect that the system will become an important communication platform for global ship traffic and 18 an important contribution to increased safety and digitisation of the shipping industry.

Kilder:
1 IMO is the International Maritime Organisation.
2 IALA is the International Association of Maritime Aids to Navigation
and Lighthouse Authorities.
3 European Conference of Postal and Telecommunications Administrations