VHF Data Exchange System (VDES) will continue to be developed over the next few years in accordance with the roadmap published in the VDES Guideline [read more]
Further information on VHF Data Exchange System (VDES) can be found in the IALA Guideline on VDES which is located on the IALA website [http://www.iala-aism.org/product-category/publications/guidelines/]If you have a question that is not answered here, please send it to email@example.com for consideration by the ENAV committee.
Current users of AIS and…
The VDES satellite component provides very large area coverage cost effectively, this is particularly important in the Polar Regions outside geostationary satellite coverage. In addition, VDES satellite can assist with coverage beyond the range of terrestrial VDES, or where VDES infrastructure does not exist.
The satellite component of VDES may increase the ship terminal adoption rate as a cost effective, global (but low capacity) capability while the terrestrial VDES is widely deployed.
As an example, NAVAREA XIX is 1500 km wide at 75 N and the North-South distance is more than 2000 km between 65 N and 85 N. This area is poorly served with affordable communications, and this is the reason Norway launched its Norsat-2 satellite with a VDES test transceiver in July 2017. Two such satellites in polar orbits would provide automatic store and forward VDES messaging for typically 10 minutes 26 times per day for latitudes higher than 70 degrees. A terrestrial VDES base station may have limited coverage range, and there are very few islands with access to the internet and power in the Arctic. Providing coverage with a terrestrial solution only would not be possible in these regions.