Research And Design Of Law Enforcement Vessels’ Intelligence Analysis And Auxiliary Decision System

With the new development of the world situation,marine security,as an important part of national security,is playing an increasingly prominent strategic role.However,China’s current maritime rights and interests are constantly being violated and maritime security is facing enormous challenges.As the carrier of China Coast Guard’s enforcement,the domestic law enforcement vessels have problems such as small tonnage,small quantity and low degree of automation,which make it difficult to be adapt to the increasingly arduous maritime tasks in the new era.Therefore,constructing law enforcement vessels’ intelligence analysis and auxiliary decision system to assist law enforcement officers in situation assessment and decision-making is of great significance to safeguard national security and maritime rights and interests.Based on the development of intelligence analysis and auxiliary decision system for a certain type of law-enforcement vessel,this thesis studies the data fusion method of AIS and radar system,analyses the target vessels’ threat degree and builds auxiliary decision model to meet the actual needs of the project.Firstly,this thesis introduces the basic architecture and message format of AIS and radar system,expounds the advantages and disadvantages of AIS and radar and completes data processing such as data extraction and field meaning analysis of AIS and radar messages.On this basis,the coordinate transformation of AIS and radar information is carried out by using Gauss-Kruger projection method,and the observation information is synchronized to the same time by using linear interpolation method of interpolation or extrapolation.Secondly,this thesis focuses on the data fusion of AIS and radar systems.By deducing and analyzing the JPDA algorithm based on single sensor(radar),the multi-sensor JPDA algorithm is studied and improved.The MSJPDA algorithm which uses sequential structure to fuse AIS and radar data is proposed and Matlab simulation is performed to draw the target trajectory and predict trajectory.It can be seen from the results of the simulation that the improved fusion algorithm significantly reduces the estimation error and performs well.Then,the thesis comprehensively considers the hostility of the target vessel to the domestic law enforcement vessel and the degree of invasion of the target ship to jurisdiction.By studying and deciding the weights of the determinants,the total model of the target vessels’ threat assessment is constructed and tested.The evaluation test shows that the evaluation result of the simulated target vessels’ threat degree is consistent with the situation.Based on the target track information and threat assessment model combined with AIS and radar,this thesis analyzes the actions that the ship should take in response to the different degrees of threat and establishes the ship maneuver according to different decision requirements.The mathematical model finally completes the ship maneuvering process simulation in a given scene,and the simulation results basically reach the expected goal.Finally,based on hardware platform built by embedded industrial computer module and multi-tasking software framework built by Vx Works embedded operating system,this thesis designs law enforcement vessels’ intelligence analysis and auxiliary decision system,which realizes subtasks such as AIS and radar message receiving and parsing,target plot fusion,target threat calculation,target sequencing,and ship maneuvering.The simulation test and on-site debugging of the system prove that it meets the requirements of law enforcement ships in terms of operational efficiency,real-time and reliability,and provides a new idea for further research on the effectiveness of law enforcement ships’ auxiliary decision system.