卫星位置误差条件下基于约束Taylor级数迭代的地面目标定位理论性能分析

基于卫星平台的地球表面目标定位系统受到卫星位置误差的影响较大,为此,该文在卫星位置存在误差的条件下,系统给出一种推导约束Taylor级数迭代公式及其理论定位性能的数学分析框架.为了便于讨论,文中以时差观测量为范例,并在三种情形下分别推导各种用于地面目标辐射源定位的约束Taylor级数迭代公式及其相应的理论定位性能,并将该理论性能与三种情形下的约束Cram′er-Rao界进行定量比较,从而得到若干定量结论.文中讨论的三种情形包括:(I)没有卫星位置误差且没有校正源的情况;(II)卫星位置存在误差且没有校正源的情况;(III)卫星位置存在误差且存在校正源(位置精确已知)的情况.最后,文中设计若干基于时差的卫星定位实验场景用以验证算法推导和理论分析的有效性.

The geolocation performance analysis for the constrained Taylor-series iteration in the presence of satellite orbit perturbations

The satellite orbit perturbations would seriously degrade the geolocation precision for the static emitter on the earth＇s surface. The mathematical analysis frame used to derive the constrained Taylor-series iteration formula and its theoretical geolocation performances are systematically presented in the presence of satellite orbit perturbations. For convenience, the time difference of arrival （TDOA） measurement is taken as an example, and the geolocation algorithms as well as the theoretical geolocation performance are deduced for three different situations. Additionally, the theoretical performances are compared with the Cram~r-Rao bound （CRB） corresponding to the three situations stated above. And several quantitative conclusions are also drawn. The three cases include： （I） neither satellite orbit perturbations nor calibration sources exist; （II） satellite orbit perturbations exis and there are no calibration sources; （III） both satellite orbit perturbations and calibration sources exist. Finally, some satellite TDOA geolocation scenarios are devised to verify the effectiveness of the geolocation algorithms and the performance analysis of this paper.