Study On System Designing And Positioning Algorithms For Land-based Multi-spot Location Based TDOA

This dissertation devotes in designing a land-based multi-spots positioning system and study on its positioning algorithms based time difference of arrivals.On the basis of introducing the SSR signal form and wireless multi-spot localization method, the system composition structure of land-based multi-spot positioning system are elaborated, the major function and working pattern of the various units in system are proposed. The performance about Geometry Dilution of Precision and the positioning algorithms based also analyzed in this dissertation.The base stations of receiving signal, clock synchronization calibrates, and central processing are chosen to be the system major body construction according to the characteristic of different frequency receiving and dispatching pattern and multi-spot wireless localization technology. The algorithms based time difference of arrivals is chosen to be the system positioning under the requirement of positioning accurate. Then, the technical solutions and simulations of the major function of the various units in system and GDOP are analyzed in details. The key technical difficulties of TODA positioning are seriously researched.With the clear target, the method of judge the signal arrival time along the sampling peak value of the downlink signal pilot pulse rise and the solution flow of synchronized clock revises error are set forth by the analysis in the major unit. Furthermore, the mathematical model, computational method, as well as minimum value scope about GDOP are set forth also. The location principle, computational method and equation set resolving by the taylor series method and the Chan algorithm of the hyperbolic curve and the hyperboloid positioning has studied in depth. One kind of method named circulation master station localization for remove the fuzzy solution and one kind of improvement mix algorithm are proposed. The results imply that proposed location system and improvement algorithm can get a high positioning precision.