ERDC researchers aid in VDES development

Published March 6, 2014
A conceptual diagram of the VHF data exchange system is depicted, showing how vessels and shore stations might communicate using terrestrial communications and how satellite communication would augment and extend the terrestrial component.

A conceptual diagram of the VHF data exchange system is depicted, showing how vessels and shore stations might communicate using terrestrial communications and how satellite communication would augment and extend the terrestrial component.

Automatic Identification System (AIS) technology is a very useful and effective tool for communicating navigation safety information on inland waterways, and the usage of AIS is rapidly expanding.  Due to this expansion, there is a possibility that the AIS VHF Data Link (VDL) will be overloaded in the future.

In response to this, several international bodies are working together to develop additional technologies to complement AIS in communicating navigation information. In support of these international developments, the Japan Coast Guard (JCG), in cooperation with the Ocean Policy Research Foundation (OPRF), held a workshop on the international standardization of ‘next generation AIS’ in Tokyo.  The workshop developed the concept of the VHF Data Exchange System (VDES) and identified many system functional requirements. Subject matter experts from several countries, administrations and industry were invited to participate, including ERDC researchers.

Brian J. Tetreault, a navigation systems specialist with the U.S. Army Engineer Research and Development Center (ERDC) Coastal and Hydraulics Laboratory (CHL), was among those invited to provide information on Corps of Engineers navigation technology related to VDES and requirements that this system could address.

“It is still somewhat conceptual how VDES will work, and there are many technical and policy details to be worked out, but the idea is that in the future AIS will be used solely for safety of navigation purposes, and additional frequencies and transmission technologies can be used for less urgent communications with higher bandwidth and fewer usage restrictions,” Tetreault said.

The ability for ships to transmit from ship to shore is important.

“Data exchange between ship and shore is critical to navigation safety and efficiency, and can also enhance waterway management and provide a more reliable navigation system. For example, bathymetry changes can be communicated quickly to vessels to allow them to safely navigate narrow channels. Ships can report more information to shore side authorities (such as cargo) that will help manage waterways infrastructure. This information will be communicated automatically and can be encrypted for security (AIS is open and unencrypted),” he said.

VDES works with AIS to ensure smoother communications.

VDES provides capabilities to transfer navigation-related information between ship and shore entities enhancing navigation safety. VDES combines "traditional" AIS (the technology that allows vessels to “see and talk” to each other around bends, and while out on the high seas) and a new data transmission technology together, using several new frequencies that are being made available for digital maritime communications.

VDES is designed to provide a higher, robust and global data exchange in the maritime VHF mobile band and its essential for countries to manage its radio frequencies.

“Each country manages radio frequencies in its area of responsibility.  It is important for global communications capabilities such as AIS and VDES that common frequencies are identified and allocated worldwide. That way a vessel sailing from Japan to the U.S. has the same frequencies available for the same type of communications,” Tetreault said.

“There are many potential uses for VDES by USACE missions, primarily any mission that requires information from vessels or that would be enhanced by communicating information to vessels,” Tetreault said.

“ Some examples are the collection of waterways usage data - currently done manually on a month-by-month basis. This data needs to be reconciled annually to create waterway usage statistics. These statistics assist USACE in determining resource allocation (i.e., dredging and construction funds). This information could be potentially transmitted in real time and more accurately from the source systems on vessels that create it, producing more accurate and timely statistics. Information USACE collects on waterway and infrastructure status (e.g., bathymetry, lock operational status, etc.) can be communicated automatically to vessels and immediately displayed on their navigation systems, allowing them to navigate more safely and efficiently. Some of this is being done with AIS, but there are limitations in bandwidth and type of information that can be communicated,” he said.

“The development of VDES is an example of the progress of navigation technologies that will help USACE and other waterway stakeholders safely and efficiently use and operate our nation’s waterways infrastructure.”


CHL