基于射线跟踪的TOA定位算法的GDOP研究

Research on GDOP of TOA Positioning Method Based on Ray Tracing

GDOP是衡量定位系统精度的一种重要指标。基于射线跟踪的定位算法利用镜像站实现对目标的定位,现有关于GDOP的计算没有考虑镜像站之间的相关性,故其无法准确反映此类算法的定位精度与镜像站布局之间关系。针对这个问题,给出一种适用于基于射线跟踪的TOA(TOA-RT)定位算法的GDOP计算方法。针对微小区TOA定位模型,根据信号传播路径及镜像原理,得到了镜像站位置误差的相关矩阵,并据此推导了TOA-RT算法的GDOP计算公式。仿真结果证明了文章所给的GDOP计算方法的有效性。

GDOP is an important parameter of the positioning system. Ray-trace-based positioning method uses image base station （I-BS） to estimate the position of target, but the existed calculation methods of GDOP don＇ t consider the correlation between the I-BSs, so it can not accurately reveal the relationship between such positioning methods and the layout of I-BSs. For this problem, this paper proposes a calculation mothed of GDOP which is suitable for ray-trace-based positioning meth- od using TOA measurements （TOA-RT）. According to the signal propagation path and the imaging principle, we can get the correlation matrix of position error of the I-BSs, and the GDOP calculation formula of TOA-RT method is derived based on the correlation matrix. The simulation results show the effectiveness of the GDOP calculation method.