Passive Radio Frequency Identification (RFID) tags have been widely applied in many applications, such as logistics, retailing, and warehousing. In many situations, the order of objects is more important than their absolute locations. However, state-of-art ordering methods need a continuing movement of tags and readers, which limit the application domain and scalability. In this paper, we propose a 2-dimension ordering approach for passive tags that requires no device movement. Instead, our method utilizes signal changes caused by arbitrary movement of human beings around tags, who carry no device for horizontal dimension ordering. Hence, our method is called Human Movement based Ordering (HMO). The basic idea of HMO is that when people pass between the reader antenna and tags, the received signal strength will change. By observing the time-series RSS changes of tags, HMO can obtain the order of tags along with a specific horizontal direction. For vertical dimension, we employ a linear programming method that is tolerant of tiny errors in practice. We implement HMO with commodity off-the-shelf RFID devices. The experimental results show that HMO can achieve up to 88.71 and 90.86 percent average accuracies in the signal- and multi-person cases, respectively.

中文翻译：

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HMO：在移动环境中使用静态设备订购 RFID 标签

无源射频识别 (RFID) 标签已广泛应用于许多应用领域，例如物流、零售和仓储。在许多情况下，对象的顺序比它们的绝对位置更重要。然而，最先进的订购方法需要标签和阅读器的持续移动，这限制了应用领域和可扩展性。在本文中，我们为无源标签提出了一种无需设备移动的二维排序方法。相反，我们的方法利用了由人类在标签周围任意移动引起的信号变化，他们没有携带水平维度排序的设备。因此，我们的方法称为基于人体运动的排序（HMO）。HMO 的基本思想是当人们从阅读器天线和标签之间经过时，接收到的信号强度会发生变化。通过观察标签的时间序列RSS变化，HMO可以获得标签在特定水平方向上的顺序。对于垂直维度，我们采用线性规划方法，在实践中可以容忍微小的错误。我们使用商品现成的 RFID 设备实施 HMO。实验结果表明，HMO 在信号和多人情况下分别可以达到 88.71% 和 90.86% 的平均准确率。