The U.S. Coast Guard (USCG) reports that the volume of marine vessels using the Automatic Identification System (AIS) has been increasing since its inception in 2000. This increase is resulting in overloading of the two channels that carry the AIS transmissions.
In response to this overloading of AIS, international organizations like the International Maritime Organization and the International Association of Marine Aids to Navigation and Lighthouse Authorities are developing the next generation AIS—called VDES, which will increase the number of channels available and utilize terrestrial and satellite communication for the exchange of safety and navigation information. VDES is a technological concept utilizing terrestrial and satellite radio communication links in the VHF maritime mobile band to facilitate globally interoperable digital data exchange between ships, between ships and shore, between ships and satellite, and between satellite and ships.
Now, the Coast Guard is presently investigating the Very High Frequency (VHF) Data Exchange System (VDES) and impacts on the Automatic Identification System (AIS).
To date, the USCG has conducted extensive work and established a robust test environment for AIS and VDES which includes communications base stations near the USCG Research and Development Center (RDC) in the vicinity of New London, CT. Through a Cooperative Research and Development Agreement (CRADA) the Coast Guard plans to leverage RDC’s terrestrially based test network of VDES base and mobile stations to demonstrate the capabilities and limitations of transmitting maritime safety information (MSI) on the satellite channels of VDES (VDE-SAT) as compared to the current AIS satellite channels. The CRADA will cover the cooperative testing of the VDE-SAT equipment, platforms, and satellite data services.
The CRADA will be used to determine how VDE-SAT could be implemented to support multiple USCG core mission areas for shore-side and shipboard use under a variety of scenarios.
Technology researched, tested, and prototyped will adhere to all active USCG, Federal Communications Commission (FCC), and National Telecommunications and Information Administration (NTIA) standards and regulations.
The USCG seeks to continue its investigation of VDES, focusing on the evaluation of the VDE-SAT component and how the system may be able to expand VDES coverage beyond the range of terrestrial VDES sites for enhanced maritime domain awareness. This investigation will evaluate the capabilities and limitations of using VDES to communicate Application Specific Messages or similar MSI (that is, International Hydrographic Organization S-124 based) with vessels operating in polar regions, offshore, or other inshore regions with limited to no VHF coverage (for example, Western Rivers).
The Coast Guard is currently seeking to identify non-federal partners that can successfully provide access to VDES satellites for test and evaluation purposes. For details, click HERE.
