一种基于菲涅尔区的免穿戴呼吸检测模型
A Device-Free Breathing Detection Model Based on Fresnel Zone
摘要: 利用无线信号进行呼吸检测已被证明具备可行性，但仍存在一些不足之处，如实验设置需要较大的空间；呼吸检测时容易受到非目标活动干扰等。本文通过数学分析方式指出最短菲涅尔区半径所在位置，并结合自由空间传播路径损耗公式和天线电磁场特征，优化了天线设置方式，提出了一种WI-BD呼吸检测模型。实验结果表明，本文所述的WI-BD模型切实可行，信道状态信息变化幅度可达4~8 dB，且具有显著优势：有效减小检测空间；获得最佳菲涅尔区半径；天线间距的可调控性有助于模型的实际应用。
Abstract: Detecting breathing with wireless signal has been proved to be feasible, but there are still some problems that should be improved. For example, the experiment usually requires a large space. Also, the experiment is vulnerable to environmental factors like surrounding people’s activities. This paper analyzes and compares the radius of the Fresnel Zone in different directions mathe-matically. We have built an optimization model for the antenna setting exploring of the classic path loss model in free space propagation and the characteristics of electromagnetic field of antennas. The results of our experiments show that the WI-BD model based on Fresnel Zone is feasible. The change range of channel state information can reach 4 - 8 dB, and the model has several significant advantages: Firstly, it effectively reduces the size of the space required by the experiments; Secondly, we can directly get the best radius of Fresnel Zone; Lastly, we can adjust the distance between the antennas to get the best performance.
文章引用：谷雨, 刘博文, 占金海. 一种基于菲涅尔区的免穿戴呼吸检测模型[J]. 无线通信, 2018, 8(3): 87-96. https://doi.org/10.12677/HJWC.2018.83010

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