TOA/TDOA非直达波定位算法研究

【作者】 刘霞；

【导师】 万群；

【作者基本信息】 电子科技大学 ， 信息获取与探测技术， 2007， 硕士

【摘要】 蜂窝网无线定位技术随着移动通信技术的大规模发展和3G时代的到来,已成为越来越活跃的研究领域,在理论和应用方面都涌现了大量的研究成果。波达时间(TOA)和波达时间差(TDOA)定位法是蜂窝网无线定位技术中应用最广泛的两种定位方法,而非视距(NLOS)传播误差是影响其定位精度的主要因素。如何降低NLOS传播的影响已成为提高定位精度的关键,也是国内外研究者关注的热点课题。直达波(LOS)基站鉴别技术是一种有效的非视距传播影响减轻技术,先鉴别出直达波基站,再利用视距传播条件下的定位算法定位。当直达波基站鉴别正确时,定位精度为LOS定位算法所能提供的定位精度。本文围绕基于直达波基站鉴别技术的抗非视距传播影响TOA/TDOA定位算法研究,做了如下三个方面的工作:1.研究了蜂窝网无线定位中视距传播条件下的TOA定位原理与定位算法,重点研究了Chan方法和近似最大似然估计法。对各种算法性能进行了仿真分析与讨论。2.改进了一种基于直达波基站鉴别技术的抗非视距传播影响TOA定位算法。这种直达波基站鉴别方法是基于近似最大似然估计技术和残差检测(RT)技术的。对改进后的基于距离残差检测(RRT)的方法与已有的基于位置残差检测(PRT)的TOA定位方法进行了理论分析与仿真比较,验证了改进的方法的优越性。3.将改进的基于RRT的抗非直达波影响TOA定位算法推广到TDOA定位系统中,提出了一种NLOS环境下基于距离差残差检测(RDRT)的TDOA定位算法。通过对提出的方法与已有非直达波抑制方法的仿真比较和分析,验证了提出的方法的优越性。更多还原

【Abstract】 Cellular wireless location technology has been a more and more active research area along with the the rapid development of mobile communication technology and the approaching of 3G age. A great deal of research results on the theory and application have appeared. Time of arrival and time difference of arrival (TOA/TDOA) based methods are two popular methods in wireless location. However, the non line of sight (NLOS) error is the major cause that degrades the location accuracy. How to suppress the NLOS error has been the key of improving the accuracy of wireless location, and also the focus of worldwide reasearchers.Line of sight (LOS) base station (BS) identification method is an effective way to minimize the effects of the NLOS contributions. It identifies and localizes with the LOS-BS. If the identification is correct, the accuracy is what the LOS localization algorithm can provide. This dissertation focuses on the research of LOS-BS identification based TOA/TDOA location algorithm under NLOS conditions and three aspect’s works were done.1. The principle and algorithm of TOA based location method are been researched. We stress on the Chan’s method and the approximate maximum likelihood localization (AML) algorithm. The algorithms are simulated and analyzed in the dissertation.2. A TOA based NLOS error suppressing method is been improved. The improved method is based on the AML estimation and the range residual test (RRT). The RRT method is simulated and compared with the present position residual test (PRT) method. The superiority of the proposed method is proved.3. A TDOA based NLOS error suppressing method is proposed, which is based on the range difference residual test (RDRT). It is the generalized method of RRT based TOA method. The proposed method is simulated and compared with the present NLOS suppressing method. The superiority of the proposed method is proved.更多还原