基于地球高程信息的运动辐射源时差频差无源定位算法

Moving source localization using TDOA and FDOA measurements in the presence of altitude knowledge

本文研究利用时差频差以及地球高程信息对运动辐射源的定位测速问题.针对高程信息精确已知的情况,提出一种鲁棒迭代约束加权最小二乘法RICWLS-noAE(robust iterative constrained weighted least squares without altitude error).方法通过引入多个辅助变量将测量方程伪线性化,而后根据加权最小二乘准则构建含4个二次约束的代价函数,最后通过将二次约束近似成伪线性约束的方式迭代求解出辐射源的位置和速度.当高程信息存在误差时,对算法进行拓展,提出RICWLS-AE(robust iterative constrained weighted least squares under altitude error)以解决对运动辐射源定位测速问题.数值仿真表明本文所提RICWLS-noAE法的定位和测速性能要好于现有的两步加权最小二乘法,并且RICWLS-AE方法在中等信噪比下也能达到CRLB.

This study investigates the moving source localization using the time difference of arrival(TDOA) and frequency difference of arrival(FDOA) measurements in the presence of altitude knowledge. A robust iterative constrained weighted least squares method is proposed for source localization with precise altitude data(RICWLSnoAE). The algorithm pseudo-linearizes the measurement equations by introducing multiple auxiliary variables.Afterward, it constructs a cost function with four quadratic constraints based on the weighted least squares criterion. The source position and velocity are iteratively obtained by approximating the quadratic constraints as pseudo-linear constraints. The algorithm is further extended to address the source localization in the presence of altitude errors(RICWLS-AE). Additionally, numerical simulations indicate the superiority of the localization accuracy of the RICWLS-noAE to that of existing algorithms, and the RICWLS-AE can achieve the Cramér-Rao lower bound(CRLB) at moderate noise levels.