Research And Application Of RFID-based Indoor Tracking Technology

The UHF RFID technology has been widely used in positioning and tracking scenarios. However, current tracking researches on RFID are mainly based on two aspects: positioning the tag through reader network and positioning the reader through tag network. In some scenarios, it is not feasible to bundle these equipments into moving targets. Therefore, it has vital significance in research on device-free tracking.The main research content of this thesis is tracking device-free target by RFID technology in two-dimensional scene. The specific works are as follows:(1) Proposed an adaptive scheduling strategy for tracking device-free target. In this strategy, we can position the moving target by measuring the tag-sampling frequency influenced by materials. We adopt the combination of static sampling and tracking sampling to minimize the interference between readers and achieve accurate real-time tracking results.(2) Proposed a method based on motion study and forecast, solving the multi-objective path separation problem. For access conflict problems in reader network and reference tag network caused by multi-target tracking, we solve them separately by adopting the multiplex merge method and speed-priority based scheduling method. It achieves the purpose of real-time tracking for multi-targets.(3) Proposed a path-filling strategy based on string matching. We transfer the path into a character array and establish a path dictionary. Then we train the probability event. We can calculate the minimum edit distance and restore the full target’s trajectory by converting path loss problem into string matching problem.(4) Designed and implemented an RFID based tracking system. We develop the prototype system combined with the above three strategies in accordance with the need of the actual scene. At last, we implement the functions including tracking, shape recovery and path filling.The experiment results show that, this thesis’ s achievement can be applied in RFID-based tracking system and it performs well. It also can be used in device-based tracking scenarios.