双频-时频信道联合指纹优化室内定位方法

A Dual-Band Time-Frequency Domain Joint Fingerprint Optimization Method for Indoor Localization

传统信道状态信息(Channel State Information,CSI)指纹定位方法存在以下难题:1)单频段或单域的CSI存在较大维度损失,指纹解译能力差;2)硬件设备的基带设计导致CSI幅度和相位失真,定位稳健性差。因此,针对当前流行的双频WiFi网卡,提出双频-时频信道联合指纹优化室内定位方法。首先通过获取双频段的CSI进行幅度和相位优化,然后从优化后的CSI中提取出双频-时频信道联合指纹。将多个样本的该指纹分别输入到定位模型进行位置候选集构造,再根据候选集合,提出可信位置选择算法,联合优化各个候选位置的核密度函数和权重,选出值得信任的位置进行加权,得到最终位置的最优估计。两个实际场景中的实验结果表明所提定位方法极大地改善了指纹解译能力,较传统方法具有更高的定位精度和稳健性。

The traditional channel state information fingerprint localization method has the following problems:1)the channel state information of a single band or single domain has large dimension loss and poor fingerprint interpretation ability;2)the baseband design of hardware equipment leads to the distortion of channel amplitude and phase,thus leading to poor localization robustness.Therefore,aiming at the current popular dual-band WiFi network card,this paper proposes a dual-band WiFi time-frequency domain joint fingerprint optimization method for indoor localization.Firstly,the amplitude and phase are optimized by obtaining the dual-band frequency-domain channel state information,and then the dual-band time-frequency amplitude joint fingerprint is extracted from the optimized channel state information.The fingerprint of multiple samples is input into the localization model to construct a candidate location set.Then,according to the candidate set,a trustworthy location selection algorithm is proposed,which jointly optimizes the kernel density function and weight of each candidate location,selects the trustworthy location for weighting,and obtains the optimal estimation of the final location.Experimental results in two real-world environments show that the proposed method greatly improves the ability of fingerprint interpretation,and achieves higher positioning accuracy and robustness than traditional methods.