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The Automatic Identification System, or in short AIS, is a digital wireless communication system, which is an essential part of modern maritime administration system. However, the complex dimensions of inland river channels make the propagations of AIS in inland rivers is quite different with that in the open sea.1) The effective range would decrease a lot. The AIS is typical VHF (Very High Frequency) sight propagation wireless equipment, the mountains and build-up areas would attenuate the signal distinctly.2) The capacity of AIS data link is not enough. The AIS system was for the application in the open sea for the first time, which would face limitation in the inland rivers. There would be full of vessels in the inland rivers and ports, which mean the channels, are not capable to maintain all the terminals.3) The design of the AIS equipments is not reliable. There is no highly intergrated IC manufacture for the AIS. Therefore, the reliability of the AIS equipments is totally related to the local manufactures. In the inland rivers, it is very common that, a large sum of B type AIS terminals reporting fault position information, which reduce the reliability of the whole AIS system. To fix the problem, the administrators have to pay lots of attention to distinguish the errors manually.To solve the problems above, the dissertation is going to do the researches below.1) Due to the complexity, there is no integrated software or hardware platform to study the reliability of AIS. The research proposes the hardware-in-loop simulation to solve the problem, which introduce the AIS equipment into the simulation environment, making the simulation process in good accordance with the filed running.2) Besides the simulations, the research builds up a field-testing platform in the Wuhan Channel, Changjiang Rivers to test the models mentioned in the research.3) With the help of the hardware-in-loop simulations, the research finds out several important micro characteristics of AIS data link, the correlation between AIS PER and the field strength, the interference description, the short messages capacity, and the AIS base band fast modulation.4) The research studies the AIS signal spreading and attenuation in certain channel in in-land Rivers, with the field strength median estimation model and ray-tracking model, and proposes the revising ray tracking method to fulfill the requirement in the different weather and dimensions, and test it in the field-testing.5) With the help of DS theory and Improved Evidence Theory Similar method, it is possible to combine the channels and motion evidences to distinguish the error AIS information. Meanwhile, by adopting the wise transmitting power, the AIS terminals would make the communication with basestations more reliable, and reduce the occupation of AIS data link.In summary, all the researches above are going to develop the micro characteristics of AIS data link, propose a new way to estimate the AIS signal field strength which is suitable in inland rivers, a new method to distinguish the fault AIS messages, an improvement for the AIS terminals to protect the AIS data link resources. By all the researches, it is able to study the AIS reliability in inland rivers, and support the other optimizations.
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