摘要： 基于WiFi的室内定位技术受天线数量和频道带宽影响，存在定位精度低和跟踪易失败的问题。为此，提出一种多参数室内无源定位技术。通过几何关系解释包括到达角、飞行时间和多普勒频移在内的参数，利用参数模型量化用户运动和信道状态信息间的关系，将多参数估计问题表示为最大似然估计问题，使用广义期望最大化算法将错误的原始参数细化到一定范围内，最终输出目标位置。实验结果表明，该技术平均定位误差为0.7 m，相较于时间与空间信号模型、指纹定位、空间域建模等现有的无源定位技术具有更好的定位精度和稳定性。

关键词: 无源定位, WiFi技术, 无线感知, 多参数, 广义期望最大化算法

Abstract: The existing WiFi-based indoor positioning technology is affected by the number of antennas and channel bandwidth, and has the problems of low positioning accuracy and frequent tracking failures.To address the problem, a multi-parameter indoor passive positioning technology is proposed.Based on the geometric relations, the parameters including Angle of Arrival(AOA), Time of Flight(TOF) and Doppler Frequency Shift(DFS) is explained.Then the parameter model is used to quantify the relationship between user motion and Channel State Information(CSI), simplifying the multi-parameter estimation problem into a maximum likelihood estimation problem. On this basis, the Space Alternating Generalized Expectation Maximization algorithm(SAGE) is used to refine the wrong original parameters to a narrow range, and finally output the target position.Both theory and simulation results show that this method reduces the average positioning error to 0.7 m, providing higher positioning accuracy and stability than existing passive positioning algorithms.

Key words: passive positioning, WiFi technology, wireless perception, multi-parameter, generalized expectation maximization algorithm

中图分类号: 

• TN99