Liu Wen, Jia Mingjie, Deng Zhongliang, Qin Changyan
School of Electronic Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China.
Entropy (Basel). 2022 Apr 25;24(5):599. doi: 10.3390/e24050599.
Channel state information (CSI) provides a fine-grained description of the signal propagation process, which has attracted extensive attention in the field of indoor positioning. The CSI signals collected by different fingerprint points have a high degree of discrimination due to the influence of multi-path effects. This multi-path effect is reflected in the correlation between subcarriers and antennas. However, in mining such correlations, previous methods are difficult to aggregate non-adjacent features, resulting in insufficient multi-path information extraction. In addition, the existence of the multi-path effect makes the relationship between the original CSI signal and the distance not obvious, and it is easy to cause mismatching of long-distance points. Therefore, this paper proposes an indoor localization algorithm that combines the multi-head self-attention mechanism and effective CSI (MHSA-EC). This algorithm is used to solve the problem where it is difficult for traditional algorithms to effectively aggregate long-distance CSI features and mismatches of long-distance points. This paper verifies the stability and accuracy of MHSA-EC positioning through a large number of experiments. The average positioning error of MHSA-EC is 0.71 m in the comprehensive office and 0.64 m in the laboratory.
信道状态信息(CSI)提供了对信号传播过程的细粒度描述,这在室内定位领域引起了广泛关注。由于多径效应的影响,不同指纹点收集的CSI信号具有高度的区分性。这种多径效应体现在子载波与天线之间的相关性上。然而,在挖掘这种相关性时,以往的方法难以聚合非相邻特征,导致多径信息提取不足。此外,多径效应的存在使得原始CSI信号与距离之间的关系不明显,容易导致长距离点的匹配错误。因此,本文提出了一种结合多头自注意力机制和有效CSI的室内定位算法(MHSA-EC)。该算法用于解决传统算法难以有效聚合长距离CSI特征以及长距离点匹配错误的问题。本文通过大量实验验证了MHSA-EC定位的稳定性和准确性。在综合办公室中,MHSA-EC的平均定位误差为0.71米,在实验室中为0.64米。