基于TDOA蜂窝网络的无线定位算法研究-通信与信息系统专业论文.docxVIP

摘要 近年来，随着手机用户的快速普及和移动通信技术的迅猛发展， 无线蜂窝网络逐渐完善。这使得利用完善的蜂窝网络经营一些要求比 较高的增值业务变得可行，手机定位即是有待开发的增值业务之一。 其基本原理是利用蜂窝网络，通过对移动台多种位置特征参数的测量 和估计，再综合各种算法进行计算，从而实现对移动台的准确定位。 在 蜂 窝 网 无 线 定 位 技 术 中 ， 基 于 TDOA （ Time Difference of Arrival，到达时间差）的 Chan 算法和 Taylor 算法是当今比较关注的 算法。在高斯信道环境下，Chan 算法优于 Taylor 算法，而在实际信 道环境下，Taylor 算法较 Chan 算法稍好，因为 Chan 算法的推导过程 是假设 TDOA 噪声服从零均值高斯分布，而将其应用到非高斯环境， 其性能要受到影响[36]。本文详细介绍了 Chan 算法和 Taylor 算法的推 导过程，并在此基础上提出了一种基于最小二乘法和 Taylor 级数展开 法的协同定位方法。 最后，将最小二乘法仿真得到的移动台位置作为 Taylor 级数展开 法的初始值，在零均值高斯分布噪声环境下进行仿真分析，并对 Chan 算法、Taylor 级数算法和本文提出的协同算法的仿真结果从多方面进 行了分析比较，结果表明，该算法能有效降低由于测量误差而带来的 定位误差。 关键字：到达时间差；泰勒级数；Chan 算法；无线定位 Abstract Recently, with the rapid popularization of mobile phone and the rapid development on technology of mobile communication, wireless cellular networks improve gradually. This makes us to use consummate network to manage some high value-added services become viable, while wireless positioning is becoming one of value-added services, which requires us to develop. The basic principle is to use cellular networks, and through the measure and estimate to a variety of locations on the characteristic parameters of mobile station, and then calculates with diversified algorithms in order to achieve accurate positioning of mobile stations. Becoming the one of technology of Cellular network in the wireless location, the algorithm of Chan and Taylor based on the TDOA (Time Difference of Arrival, arrival time difference) is popular. In the environment of Gaussian channel, Chan algorithm is better than Taylor. But in the actual channel environment, Taylor algorithm is better than Chan algorithm, as derived process of Chan algorithm is based on the assumption of TDOA noise obeying zero-mean Gaussian distribution, and its capability is affected when it is applied to non-Gaussian environment. This paper describes the deriving processing of the Chan algorithm and Taylor algorithm, and raises a new cooperative locating algorithm based on the least squares met