利用外辐射源的TDOA和FDOA目标定位算法  

TDOA and FDOA location algorithm using illuminators of opportunity

作　　者：赵勇胜[1] 赵闯[1] 赵拥军[1] ZHAO Yongsheng;ZHAO Chuang;ZHAO Yongjun(School of Navigation and Aerospace Engineering, PLA Information Engineering University, Zhengzhou 450001, China)

机构地区：[1]解放军信息工程大学导航与空天目标工程学院,郑州450001

出　　处：《计算机工程与应用》2017年第8期50-56,共7页Computer Engineering and Applications

基　　金：国家自然科学基金(No.61401469;No.61501513);国家高技术研究发展计划(863)(No.2012AA7031015)

摘　　要：针对单站外辐射源条件下的目标定位问题,提出了一种基于最大似然的时差-频差联合定位算法。首先根据时差和频差的观测方程,构建目标位置和速度的最大似然估计模型。然后采用牛顿迭代算法对最大似然估计模型求解,得到目标位置和速度估计。最后,推导了算法的克拉美罗界和理论误差,并证明了二者相等。仿真结果表明,算法定位精度高于两步加权最小二乘算法和约束总体最小二乘算法,在测量误差较高时仍能达到克拉美罗界。通过对系统几何精度因子图的分析,确定目标及外辐射源数量和位置也是影响定位精度的重要因素。To solve the single-observer passive location estimation using illuminators of opportunity,a jointing TDOA and FDOA location algorithm based on maximum likelihood is proposed.Firstly,according to the TDOA and FDOA measurement equations,the maximum likelihood model is constructed.Then Newton’s method is applied to solve the maximum likelihood model to obtain the estimation of the target position and velocity.The initial iteration value is given by a Least Squares(LS)algorithm.The Cramer-Rao Lower Bound(CRLB)and the theoretical error of the proposed algorithm are also derived and they are proved equal.Simulation results show that the proposed algorithm has higher estimation accuracy than the Two-Step Weighting Least Squares(TSWLS)algorithm and the Constrained Total Least Squares(CTLS)algorithm,which makes it possible to achieve the CRLB at moderate noise level before the threshold effect occurs.Moreover,fromthe Geometric Dilution Of Precision(GDOP)figure,it concludes target position,illuminator number and position are also important factors affecting the localization accuracy.

关 键 词：无源定位 到达时差 到达频差 最大似然 牛顿迭代 最小二乘 

分 类 号：TN971[电子电信—信号与信息处理]