VDES (VHF Data Exchange System) is the second generation of the popular AIS technology used for vessel tracking and other navigational and safety-related purposes by more than 200,000 vessels globally. As illustrated below, AIS allows ships to broadcast their position (along with id, course, and speed). This is picked up by other ships, by coastal VHF radio networks, and today also by satellites.

Over the past decade, the maritime industry and authorities have identified needs for more digitalization. This has been captured in the IMO e-Navigation strategy. The figure below illustrates a number of needs for both incoming, outgoing, and two-way digital communication.

VDES is the new communication solution to implement the e-Navigation strategy. VDES is an extension to AIS, adding two-way data channels over VHF. By using special satellite channels (up and down), every ship with a VHF antenna is able to communicate globally. This figure illustrates a few VDES services such as “Ice charts”, “Engine monitoring”, and “Environmental monitoring” using smart buoys.

The VDES system consists of these two sub-systems working together:

  1. VDE-TER: The terrestrial sub-system (ship-to-ship and shore-to-ship), and
  2. VDE-SAT: The satellite sub-system (satellite-to-ship).

Sternula will be developing the VDE-SAT infrastructure enabling VDES on a global scale from 2022.