基于信道状态信息测距的Wi-Fi室内定位误差界分析方法

相较常用于室内定位的Wi-Fi接收信号强度(RSS)，Wi-Fi信道状态信息(CSI)包含了信号传输过程中更细粒度的物理层信息(如各个子载波的幅值和相位)，故可将其用于较精确的测距以实现较高的Wi-Fi室内定位精度。由于现有基于CSI测距的定位方法普遍缺少关于定位误差界的理论分析，从而导致难以对不同定位方法的理想性能进行比较。因此，该文提出一种基于CSI测距的Wi-Fi室内定位误差界分析方法，其在室内信号传播模型的基础上，考虑路径损耗、阴影衰落和多径效应与定位精度的关系，利用克拉美罗下界(CRLB)推导了时钟异步效应下基于CSI测距的定位误差界。此外，通过实验对比，分析了实际定位误差与所推导的定位误差界之间的差异，并讨论了不同实验参数对定位性能的影响。

Wi-Fi Indoor Localization Error Bound Analysis Method Based on Channel State Information Ranging

Compared with the Wi-Fi Received Signal Strength (RSS) commonly-used for the indoor localization, the Channel State Information (CSI) can be used for the precise ranging to achieve the high Wi-Fi indoor localization accuracy since it includes the fine-grained physical-layer information such as the amplitude and phase of each subcarrier during the signal transmission. Due to the lack of theoretical analysis of the localization error bound in existing CSI ranging-based localization methods, it is difficult to compare the ideal performance of different localization methods. Therefore, a CSI ranging-based Wi-Fi indoor localization error bound analysis method is proposed, which is based on the indoor signal propagation model to derive out the CSI ranging-based localization error bound with the clock asynchronous effect by considering the relationship between the localization accuracy and the path loss, shadow fading, and multipath effect. Besides, through the experimental comparison, this paper analyzes the difference between the actual localization error and the derived localization error bound, as well as discusses the impact of different experimental parameters on the localization performance.