无源时差定位技术及应用研究

【作者】 江翔；

【导师】 魏平；

【作者基本信息】 电子科技大学 ， 信号与信息处理， 2008， 硕士

【摘要】 无源定位是指测量站不向目标发射电磁波,仅通过接收目标辐射源所辐射、反射和散射的电磁波来确定目标的位置。相对有源定位,无源定位可以更有效地抗击电子干扰、隐身技术、反辐射武器等威胁,且无源定位可以对干扰源、手机、电台等辐射源进行定位。现在无源定位中的时差(TDOA)定位技术尤其受到广泛关注,因为其具有精度高、易组网实现、能对付宽带低谱密度信号等优点。本文对时差定位技术进行了比较全面的分析研究,包括定位算法、精度分析、模糊无解、应用系统设计等内容,最后还对外场初步实验的情况和结果进行了分析。本文具体工作如下:首先,对基本时差定位技术中的定位算法、精度分析、模糊无解进行了研究。给出了TDOA双曲线模型,对Chan、泰勒级数展开、AML等几种主要的定位算法进行了推导分析,并通过仿真得到了它们在不同条件下的定位性能,找出了存在的问题;对时差测量误差和站址误差对定位精度的影响进行了分析,仿真了多种布站形式下的GDOP分布,并专门分析了目标高度对平面三站时差定位精度的影响,得出了计算定位误差模和方向的表达式;研究了平面三站情况时存在的定位模糊和无解问题,得出了其分布区域。其次,对TDOA定位技术在卫星对地观测定位上的应用进行了详细的研究。研究集中在受地球面限制的TDOA定位技术,分别介绍了正球体和WGS-84椭球体两种地球模型下的几种定位算法,并在此基础上本文提出了一种在WGS-84模型下已知目标海拔高度信息时的新定位算法,对各种算法的定位性能进行了仿真;对于影响星载受限TDOA定位精度的各种因素本文也进行了详细分析,并对误差分布情况进行了仿真。接着,针对当前的无线电监测定位系统存在的问题,本文设计了一个采用TDOA定位技术,并基于小型接收机网络的无线电监测定位系统,对系统方案、小型接收机设计及处理流程进行了介绍。最后,做了外场三站时差定位初步实验,对实验方案及数据处理方法进行了介绍,并对结果进行了分析。更多还原

【Abstract】 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.更多还原