几何精度衰减因子对两种到达时间差算法定位精度的影响分析  

Influence of Geometric Dilution of Precision on Positioning Accuracy of Time Difference of Arrival with Two Classic Algorithms

作　　者：严宏基 舒红[1] 孙红星[1] YAN Hongji;SHU Hong;SUN Hongxing(State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 430079,China)

机构地区：[1]武汉大学测绘遥感信息工程国家重点实验室,湖北武汉430079

出　　处：《测绘地理信息》2020年第3期61-65,共5页Journal of Geomatics

基　　金：国家重点研发计划(2016YFB0502204)。

摘　　要：不同几何布局下Chan算法和Taylor算法的定位精度的对比及定位精度的克拉美罗下界(Cramér-Rao lower bound,CRLB)的接近程度尚未得到分析验证,本文仿真了三维场景下几何精度衰减因子(geometric dilution of precision,GDOP)对两种算法定位精度的影响,分析了影响差异的数值计算原因。推导表明,两种算法的理论定位精度受GDOP值的影响相同,可以达到CRLB。然而,仿真结果显示,Chan算法的实际定位精度容易在CRLB上方波动,Taylor算法的实际定位精度则稳定在CRLB附近;相同GDOP值下,Taylor算法的实际定位精度优于Chan算法,Chan算法的实际定位精度随着GDOP值的增大逐渐偏离CRLB。将Chan算法和Taylor算法结合,可以有效提高Chan算法的实际定位精度。The comparison of the positioning accuracy of the Chan algorithm and the Taylor algorithm in different geometric layouts and their approximations to the Cramér-Rao lower bound(CRLB) have never been clarified.To address this issue, the influence of Geometric Dilution of Precision(GDOP) in the three-dimensional scene on the positioning accuracy of two algorithms is simulated,and the numerical calculation reason of the difference is analyzed.It is theoretically proved that the positioning accuracy of two algorithms is identically affected by a certain GDOP value, and the same CRLB can be achieved. However, the simulation results show that the actual positioning accuracy of Chan algorithm is easy to fluctuate above CRLB, and Taylor’s actual positioning accuracy is stationary at the CRLB. With the same GDOP value, the actual positioning accuracy of Taylor algorithm is better than that of Chan algorithm. With the increase of GDOP value,the actual positioning accuracy of Chan algorithm gradually deviates from CRLB. With the help of Taylor algorithm, theactual positioning accuracy of the Chan algorithm can be largely improved.

关 键 词：GDOP值 Taylor算法 CHAN算法 克拉美罗下界 定位精度 

分 类 号：P208[天文地球—地图制图学与地理信息工程] P228[天文地球—测绘科学与技术]