当今社会人口老龄化进程急剧加速，老年人的家庭护理需求日益增多。摔倒作为独居老人的室内活动主要健康威胁，已经引起了健康看护机构和社会的密切关注。在这种社会背景下，摔倒检测系统的需求也变得日益迫切。目前所使用的摔倒检测系统，部分需要复杂的设备搭建，另一部分则需穿戴，而这些都会对老人的日常生活造成干扰，其使用具有局限性。在本文中我们通过无线信号检测室内摔倒动作，利用信道状态信息（CSI，Channel State Information）的特点，有效的弥补了以上不足。

       本文对基于 CSI的室内人体摔倒检测策略进行了研究与分析。主要体现在细粒度的 CSI动作感知指纹库的构建，以及人体摔倒检测策略的设计这两个方面。
       本文的主要贡献可以总结为以下几点：
（1）建立了基于 CSI的细粒度动作感知指纹库。聚焦于人体动作的信息区间，通过分析 CSI的幅值和相位信息特点，以及其对室内无线感知策略设计的影响机理，建立了能初步利用信道状态信息幅度、相位特性的无线感知指纹库；
（2）设计了一种基于动作指纹库的摔倒检测策略。利用多入多出（MIMO）技术及空间分集特性提供的信息，实现权重投票融合。结合获取到的无线感知数据与分类识别相关理论，设计了单人体摔倒检测系统；
（3）在考虑各种环境因素的条件下进行了广泛的验证实验。基于以上理论研究结果，提出了基于实测数据的改进实用方案。

       通过本文的研究有助于，在理论上初步揭示 CSI和 MIMO 技术在无线环境感知应用中的性能潜力，并探索基于 CSI的室内人体摔倒检测策略的可行性。在实践方面，设计了具有高可用性的无线感知与人体摔倒检测策略。

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