Development and analysis of AIS applications as an efficient tool for vessel traffic service

Automatic identification system (AIS) has been made mandatory onboard SOLAS vessels. Most Coastal States are currently making arrangements to receive, analyze and act upon AIS data. According to the IMO Performance Standard, "AIS should improve the safety of navigation by assisting in the ...operation of Vessel Traffic Services (VTS)". However, the effectiveness of AIS as a VTS tool for traffic management and information service depends heavily on the quality of AIS information and intelligent applications for information processing, integration, and presentation. The use of AIS implies that GNSS and electronic charts (ENC) have finally started to play their roles in VTS. This paper analyzes the performance of AIS, identifies the promising benefits as well as the limiting factors. AIS application systems developed to maximize the use of AIS in VTS will then be presented. The analysis of AIS performance as a VTS tool is based on long-term continuous observations of real AIS messages around Keelung Harbor of Taiwan. Issues covered in this paper include the reliability and accuracy of GNSS-based dynamic AIS information, provision of DGNSS, availability and accuracy of static/voyage related AIS information, design of electronic charts (ENCs) for VTS, as well as the display aspects of the AIS and chart information. The AIS application system presented in this paper is developed in the ENC research Center and Mobile Information Lab. of National Taiwan Ocean University