Study On AIS And Radar Information Fusion Based On Fuzzy Comprehensive Function

Our country is one of the largest maritime countries. As the economy continues to develop, radar and AIS have become increasingly important in maritime security. Radar has independent and comprehensive monitoring capabilities on the ship’s navigational surrounding environment, whose function still can not be replaced; while AIS is a new navigational system, which plays a significant role on improving the safety of navigation. Therefore, AIS and radar information fusion has complementary advantages, which is to be an inevitable trend in shipping safety technology development.This paper analyses the difference between AIS and radar information, and studies the theory of fuzzy mathematics to identify feasible fusion algorithm between AIS targets and radar target information. This paper uses fuzzy comprehensive function to integrate information. This study can be divided into the following three phases:The first phase is to track information for pretreatment. First step is the coordinate transformation, and makes the AIS and radar information in a unified coordinate system; then make the time and space primary association judgment to eliminate most irrelevant vessel information, narrowing the scope of the judgment; finally is the time calibration, and normalizes time to the sensors whose time interval is shorter. Then it uses cubic spline function to get the AIS and radar data at any time. The second phase is the senior track association decision. It uses square difference of speed, bearing, distance and course as a single factor fuzzy set, and applies combination of factors as fuzzy evaluation algorithm for advanced correlation judgment, then selects cauchy distribution function as a membership function, which increases the flexibility of the judgment. The third phase is the associated data fusion. It fuses radar and AIS data with the optimal weighted fusion algorithm after judgment of senior associate for the same vessel, and uses recursive least squares to the data for further processing and reduces errors.This paper uses computer programming Visual C++programming tools to achieve AIS and radar information fusion algorithm. And then uses of related algorithms to display AIS and radar fused information in the electronic chart. The accuracy of fused aynamic information is improved than radar and AIS target information which demonstrates that the proposed fusion algorithm is correct and feasible.