Device-free (DF) localization is an emerging technology that allows the detection and tracking of entities that do not carry any devices nor participate actively in the localization process. Typically, DF systems require a large number of transmitters and receivers to achieve acceptable accuracy, which is not available in many scenarios such as homes and small businesses. In this paper, we introduce MonoStream as an accurate single-stream DF localization system that leverages the rich Channel State Information (CSI) as well as MIMO information from the physical layer to provide accurate DF localization with only one stream. To boost its accuracy and attain low computational requirements, MonoStream models the DF localization problem as an object recognition problem and uses a novel set of CSI-context features and techniques with proven accuracy and efficiency. Experimental evaluation in two typical testbeds, with a side-by-side comparison with the state-of-the-art, shows that MonoStream can achieve an accuracy of 0.95m with at least 26% enhancement in median distance error using a single stream only. This enhancement in accuracy comes with an efficient execution of less than 23ms per location update on a typical laptop. This highlights the potential of MonoStream usage for real-time DF tracking applications.

中文翻译：

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MonoStream：最少硬件的高精度无设备 WLAN 定位系统

无设备 (DF) 定位是一项新兴技术，它允许检测和跟踪既不携带任何设备也不积极参与定位过程的实体。通常，DF 系统需要大量的发射器和接收器才能达到可接受的精度，这在家庭和小型企业等许多场景中是不可用的。在本文中，我们将 MonoStream 介绍为一种准确的单流 DF 定位系统，它利用丰富的信道状态信息 (CSI) 以及来自物理层的 MIMO 信息，仅通过一个流提供准确的 DF 定位。为了提高其准确性并实现低计算要求，MonoStream 将 DF 定位问题建模为对象识别问题，并使用一组新颖的 CSI 上下文特征和技术，其准确性和效率已得到证实。在两个典型的测试台上进行的实验评估，与最先进的技术并排比较，表明 MonoStream 可以达到 0.95m 的精度，仅使用单个流的中值距离误差至少提高 26% . 这种准确性的提高伴随着在典型笔记本电脑上每次位置更新的有效执行时间不到 23 毫秒。这突出了 MonoStream 用于实时 DF 跟踪应用程序的潜力。95m 仅使用单个流的中值距离误差至少提高 26%。这种准确性的提高伴随着在典型笔记本电脑上每次位置更新的有效执行时间不到 23 毫秒。这突出了 MonoStream 用于实时 DF 跟踪应用程序的潜力。95m 仅使用单个流的中值距离误差至少提高 26%。这种准确性的提高伴随着在典型笔记本电脑上每次位置更新的有效执行时间不到 23 毫秒。这突出了 MonoStream 用于实时 DF 跟踪应用程序的潜力。