【作者】 魏晓莉；

【导师】 刘宏立；

【作者基本信息】 湖南大学 ， 电路与系统， 2005， 硕士

【摘要】 随着全球移动通信技术的迅猛发展,人们对移动通信业务的需求亦日益增强,其中的增值业务引起了社会的广泛关注,而定位服务则是增值业务中关注的焦点。因为有了定位服务系统,人们可以随时随地确定自己的方位,实现车辆导航,构建智能交通系统,甚至可以延伸到生活咨询服务等领域。目前,对蜂窝无线定位技术的研究还很不成熟,有许多难题亟待解决,其中的一个主要难题就是如何提高定位的精度。 本文首先综述了蜂窝网络无线定位技术的基本原理,并在分析影响定位精度的关键因素——非视距(NLOS)误差的基础上,提出了基于到达时间(TOA)的三基站定位算法、多基站联合定位算法和多基站动态定位算法,这些算法利用NLOS误差对于TOA是一个正的附加延时超量特性,采取求几何中心的方法来实现对移动台的定位,通过将这些算法与加权最小二乘法进行仿真分析表明,以上算法明显地减小了NLOS误差的影响,提高了定位精度。文章最后对TOA定位算法在GSM网络中的实现方案进行了探讨,该部分研究了GSM网络定位系统的构架,并在此构架的基础上,根据TOA定位测量的特性,增加了一些定位模块,来实现减小NOLS影响的TOA定位算法,通过与其它定位方法的比较可知,TOA定位算法不仅在方法和原理上简单,而且易于实现,对于GSM网络是一种较为理想的定位算法。更多还原

【Abstract】 With the rapid development of the global mobile communication, the demand of the people to the mobile communication business is increasing. Increment business are drawn much attention. Location service (LS) is a hotspot in all these business. Because the location system is applied, the position will be known at anytime and anywhere. It can be used in vehicle navigation and even intelligent transportation system will be constructed. Meanwhile location system can be extended to other fields such as life counseling. Currently, the study in wireless location is not mature. Many problems in the location technology are urgent to be solved. In all these problems, the improvement of the location accuracy is the key.In this paper, the wireless channel environment and the basic location technology are firstly studied. Then more attention is paid to the Non-Line-of-Sight (NLOS) error which is the most key factor which influences the location accuracy. At last, time of arrival (TOA) location algorithm for three base stations (BS), multiple BS united location algorithm and multiple BS dynamic location algorithm are put forward. All these algorithms are based on the basic character of the NLOS error ( NLOS error is always positive in TOA measure). The position of the mobile station is got after finding the center of the TOA geometry model. Through comparison with WLS arithmetic, it proves that all these algorithms mitigate NLOS error efficiently and improve location accuracy actually. At last how to apply The TOA method in the GSM network is discussed. In this part the structure of the GSM is studied, then according to the character of the TOA location measure, some location modules are added in the GSM system. The TOA method for mitigating the NLOS error is implemented. Finally, we compare several methods with the TOA method in GSM network, and the results show that TOA method is an ideal location method in GSM network.更多还原