基于波形边缘检测的Wi-Fi室内定位信号TOA估计  

TOA Estimation of Indoor Localization by Wi-Fi Signal Based on Waveform Edge Detection

作　　者：马栋榉 李敏 张端金[1] MA Dongju;LI Min;ZHANG Duanjin(School of Information Engineering, Zhengzhou University, Zhengzhou 450001, China;Institute of China Electronic Equipment System Engineering Corporation, Beijing 100141, China)

机构地区：[1]郑州大学信息工程学院,河南郑州450001 [2]中国电子设备系统工程公司研究所,北京100141

出　　处：《郑州大学学报（工学版）》2022年第3期15-20,共6页Journal of Zhengzhou University（Engineering Science）

基　　金：国家自然科学基金资助项目(61471323);中国博士后科学基金资助项目(2016M602986)。

摘　　要：为了实现室内目标的精准定位,研究基于Wi-Fi设备的信号到达时间(TOA)参数具有重要意义。常用TOA估计方法主要存在估计偏差、算法复杂以及不具有普适性等问题。针对现有方法的缺陷,提出了一种新的TOA估计方法。该方法对Wi-Fi信号波形进行采样,采用空-频-时三维搜索算法,计算某一子载波间隔一个采样周期的相邻区间分别对应的信道状态信息的相位差,通过相位差判断计算信道状态信息值的信号处理区间是否进入波形边缘,得到TOA的估计值。数值仿真结果表明:在信噪比SNR超过25 dB时,本文方法获得亚米级精度的概率超过58%;随着Wi-Fi信号带宽的扩展,本文方法能够显著提升室内定位性能。本文方法克服了传统方法的缺陷,为信号到达时间估计提供了一条新的思路。To locate the target indoor precisely,it was important to investigate on the Wi-Fi based indoor localization parameter,namely,time of arrival(TOA).The main weakness of primary TOA estimation methods were estimation bias,complex algorithm,and lack of universality.The new method had a clear physical meaning,and could pave a new way for the TOA estimation.According to the weakness of these traditional methods,a new TOA estimation algorithm was proposed in this paper.Based on sampling of waveform,the space-frequency-time searching algorithm,this algorithm calculated the phase difference between adjacent CSI calculation time span,and judged whether the CSI calculation time span could reach the edge of waveform,as to get the result of TOA estimation.Numerical results showed that the new method could achieve more than 58%submeter-level precision when the signal-to-noise ratio was above 25 dB.Moreover,the performance of the method upgraded as the bandwidth of the Wi-Fi signal expanded.The new method could overcome the weakness of traditional method,and pave a new way for the TOA estimation.

关 键 词：信号到达时间 室内定位 波形边缘检测 WI-FI 信道状态信息 相位信息 

分 类 号：TN929.5[电子电信—通信与信息系统]