The Study Of Marine Mobile Phone Location Technology Based On Ship-borne Mobile Base Station

With modern mobile communication network coverage more and more extensive, mobile phone as a daily communication tool has been widely used in maritime transport and production life. In order to further enhance the application of mobile phones at sea, Ministry of Transport of China has present that through the use of ship-borne base station implement mobile communication signal coverage at sea, and with Ministry of Information Industry jointly issued a notice, required all marine salvage department get full use of the location function of existing mobile communication, establish maritime search and rescue assistance linkage mechanism for the safety of life and property at sea. Therefore, the research of mobile location technology at sea is very important for the protection of life and property at sea and maritime search and rescue.This paper first details the existing wireless location methods and classical TDOA location algorithm, and made simulation and performance comparison for the Fang algorithm, Chan algorithm and the Taylor series expansion method in Gaussian noise environment and the COST259 channel environment. The results show that Chan algorithm has the best performance in the Gaussian noise environment, can effectively eliminate the affect of Gaussian noise on location performance, but the Chan algorithm most affected by the NLOS propagation. In the COST259 channel environment, the ideally Taylor series expansion method is better than Chan algorithm, in the marine environment, because NLOS not obvious, the performance of Taylor algorithm is slightly better than Chan algorithm. The research of classical algorithm has instructive effect for selecting appropriate maritime mobile positioning algorithm.And then aim at the ship-borne Base Station has direction finding function and mobility features, proposed by repeated sample collection the TOA and AOA information of target phone at sea to achieve single station location by TOA/AOA technology based on the existing algorithms combining with the most commonly used single-ship search and rescue model, In the case of sampling enough and not consider the move of target phone, this algorithm can get a high precision. At the same time, achieve the multiple base stations integrated location algorithm by adding AOA-finding information in Chan algorithm and the Taylor series expansion method. Proposed by TDOA/AOA location technology based on Chan algorithm and the TOA/AOA dynamic location technology provides an initial position of the target phone for Taylor series expansion method to achieve target mobile location. The simulation results show that the algorithm has better location performance.At last, give the initial idea of mobile phone location system based on ship-borne base station, proposed by adopting satellite communication system for the connection of ship-borne base station and land mobile communication network, using application software based on electronic chart implement the search and rescue ships and target phone visual display, and made the involved mobile phone location algorithm applied to the actual system.