Research And Design Of Automatic Identification System Data Communication Based On Wireless Local Area Network

With the development of the international economy and the more communication between different countries, more importance is given to the navigation technologies. 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 communication technology, computer technology and net ware technology supports the needed technology of AIS (Automatic Identification System ) . As the ever increasing need of the aiding service of the navigation, AIS is born to live and will be stronger and stronger.Automatic Identify System equipment is used on the ship, which makes the navigation safety and efficiency of shipping raise greatly. But the price of AIS equipment is relatively expensive, and the ships less than 300 tons are not required to install AIS by force by International Maritime Organization (IMO ).In this case, ships that are installed AIS can't communicate with that are not. As a result, there are safety problems. So this thesis puts forwards AIS system based on Wireless Local Area Network (WLAN ), which can be a good supplement for the existing AIS used on the inland river and near sea ships.The AIS in this thesis fully utilizes the WLAN, which puts up a wireless communication platform. Then through Winsock technology, we can connect the ship with the control center. The control center gets the information of the ship without AIS through WLAN and at the same time gets the information of the ship with AIS through the AIS station. In this way, the control center can get the information of all the ships. Then the control center analyses the information classifications, transmits information to relevant ship by WLAN.This thesis studies the system instruction of AIS based on WLAN. It puts forward safe measure for AIS used share-key attestation and WEP encrypt. Then it utilizes Visual Basic 6.0 to be the developing instrument and analyses the AIS information, connect the ship with the control center by Winsock. Sending and receiving message according to message format of AIS makes the control center can watch all ships states in real time. The ship without AIS and that with AIS can see each other. They can avoid crashing and navigate effectively. With the ship information database, we can add, change, delete and search ship information conveniently.