The Research Of The Automatic Identification System And The Key Technologies

With the development of the economy of international and the more communication of the countries, the navigation gets a chance to have a booming future. The navigation technologies are more and more to be emphasized.During the last century, the VHF (Very High Frequency) communication has been applied in the ship's transportation, as well as radar and ARPA also could identify ships in the marine. But they couldn't adapt to the needs of the modern navigation because of their limits.The rapid development of the digital communications technology, computer technology and net ware technology supports the needed technology of AIS (Automatic Identification System). As the aiding service of the navigation, AIS is born to live and will be stronger and stronger. AIS works on the marine VHF, use the SOTDMA (Self Organized Time Division Multiple Access) data chain protocol to transfer data of ships. The AIS can help the limits of the current services, and decrease the collide case of ships, and improve the value of the safe action in marine, and make the content of the radar and the VTS more stronger.Many foreign countries have already taken on the AIS for several years. The rule of AIS is update continually. But in our country, the research is just to start, so the information is limited. In order to keep up with the international development trends of AIS and master the application of AIS technology, this article researches the communication operator of the AIS, which focus on the communication and encoding technology of data link layer of the OSI (Open System International). This article also builds a testing simulation system, which can propose a software way for the latter research of AIS technology. The achievement of this thesis is shown as follows :1. This paper focuses on the researching of the transmission protocol of AIS. It analyses the relation of the four data link control protocols according to their application, and the emphasis of which is the slot reservation scheme of SOTDMA, put forward the software simulation programme and thedemonstration.2.The mode of launching data is buffering-blustering, which require the digital coding technology must work in SOTDMA . This article proposes the software programme of the data error-checkout technique CRC-16 to achieve the communication quality.3. The AIS simulation system is multiple-ships transportation, applies in ship-ship communication mode. This simulation system is composed by the ship-borne AIS and server application. The server application completes the slot synchronization and solves the bluster, the shipborn AIS can simulate many kinds of work status, realizes the communication.