Passive Tdoa Location Technology And Applied Research

The definition of passive location is that measurement-stations do not radiate electromagnetic wave towards objects and locate objects only by receiving electromagnetic wave from radiant points. Relative to active location, passive location can withstand various menaces more effectively, such as electronic interference, stealth technology and anti-radiation weapons; furthermore, passive location can locate these radiant points of electronic interference, mobile telephone and broadcasting. The TDOA location technology in passive location is payed extensive attention especially, because it has many strongpoints, such as high accuracy and easy engineering realization. This paper studies the TDOA location technology in many aspects, including location algorithms, accuracy analysis, the problems of ambiguity and non-solution, applied system design and so on. Finally, the results of the initial outfield data-collection experiment are analyzed. The detailed works are as follows:First of all, location algorithms, accuracy analysis and the problems of ambiguity and non-solution in basic TDOA location technology are studied. The mathematical model of TDOA hyperbolic equations is established, the several major location algorithms, namely Chan, Taylor-series expansion and AML, are analyzed in detail, location performance in different conditions is obtained based on simulations. The impacts that TDOA measurement error and location error of measurement-station bring to location accuracy are analyzed, and the GDOP distribution in several measurement-station layouts is simulated. The object height's impact on 2D tri-station TDOA location is analyzed especially, the equations that calculate location error and its direction vector are obtained. The problems of ambiguity and non-solution in 2D tri-station are also studied, and their distribution regions are obtained.Secondly, the application of TDOA location technology to satellite location is studied in detail. Several location algorithms in two models of the sphere and the WGS-84 oblate spheroid are introduced, and based on these algorithms, a new location algorithm in WGS-84 model when object's altitude is known is brought forward. Location performance of these algorithms is obtained by simulations. Diversified factors that influence satellites TDOA location are analyzed, and the error distributions are simulated.Thirdly, in the face of problems in current radio monitoring location system, a new radio monitoring location system which adopts TDOA location technology and bases on minitype receiver network is designed in this paper. The system scheme, minitype receiver design and processing flow are introduced detailedly.Finally, an initial outfield tri-station TDOA location experiment is done, the experiment scheme and method of data processing are introduced, and then the results of data processing are analyzed.