Abstract
Nowadays, global navigation satellite systems (GNSS) play the main role in navigating and positioning of marine vessels. However, in order to overcome the risk of weak signals of GNSS, another positioning system should be recommended as the backup system. In marine vessels, an automatic identification system (AIS) is used to provide voyage information and vessel information such as: MMSI (Maritime Mobile Service Identify), speed over ground, ship position, course over ground (COG), heading for collision avoidance and vessel traffic tracking. Inspite of the fact that AIS is a communication system, the parameters of AIS signals could be used to calculate the position of the vessel. Therefore, this paper proposes the new method for marine vessel positioning based on AIS signals. The positioning progress is implemented based on receiving the AIS signals emitted from at least three AIS base stations reached to AIS receiver on the marine vessel thanks to time-of-arrival (TOA) methodology. The measuring error of TOA method is assessed by Cramer-Rao Lower Bound (CRLB). Simulation results showed the various effects to the performance of the TOA method with AIS signals.