ARNS: Adaptive RFID Network Scheduling for Device-Free Tracking

In many RFID applications, we conduct a RFID reader network to monitor a large number of tagged items. We also want to utilize this network to trace un-tagged items. In this paper, we propose ARNS-Adaptive RFID Network Scheduling scheme for device-free tracking. In particular, we firstly deploy a set of readers and reference tags into the monitored area. Then, we divide the tags within the read region of a reader into two groups, one in reader-to-reader collision area while the other not. We monitor the area by normal sampling model in which we need two phases to separately query the two groups. When an un-tagged target appears in the monitored area, we adopt tracking sampling model. In tracking sampling mode, the reader who detects the tags´ frequency variations will adaptively query all tags in its read range to obtain the target´s full trace. Meanwhile, we fill the missing path using shortest-path algorithm to recovery the trajectory. Experimental results show that ARNS achieves high tracking accuracy for certain applications.