Structure Analysis And Simulation Designation Of MLAT System

The Multiliteration system can be able to solve the limited coverage problem of traditional radar surveillance system, and it also can make up locate failure problem of ADS-B system in some special cases. The author research the working principle and structural unit of MLAT system, put forward a feasible system design scheme, and research the key technologies including time synchronization technology, pulse signal arrival time measurement technology, and optimal stations layout based on adaptive genetic algorithm.The main contents of this paper include:1. The structure and performance analysis of MLAT system. Firstly the author introduced the structure units of system and its signal processing, classified the system according to the TDOA access method, analyzed the system performance and operation environment, studied the quality control of system including quality assurance measures and error control at last.2. The research of the system key technology. By analyzing the measuring accuracy and defects of the traditional pulse arrival time measurement technology, the matched filtering method that based on the technology of enhancing SNR to realize the pulse signal arrival time measurement was chosen, and the method of matched filtering method with multiple pulse string was proposed on that basis; the working principle of several kinds of time synchronization technology was researched, GPS common-view method was determined to realize the time synchronization of stations by analyzing and comparing their synchronization accuracy together with the advantages and disadvantages.3. A technical solution that can be implemented was proposed. Each unit of system,including the station(radio frequency processing module and digital signal processing module), time synchronization unit, central processing unit and the system communication interface were designed.4. The designation of stations layout of system. Two important factors, GDOP and CLRB,of MLAT system were analyzed, and a optimal embattling scheme based on adaptive genetic algorithm was proposed. The author made some improvements of adaptive genetic algorithm and took the GDOP and CLRB as numerical analysis tools, got the stations positions by iterative calculation, simulated and analyzed the distributions of GDOP value and CLRB value under the corresponding stations layout.