Fault-Tolerant RFID Reader Localization Based on Passive RFID Tags

With the growing use of RFID-based devices, there are increasing attentions on utilizing RFID technology for localization. In this paper, we consider RFID reader localization which locates an object by attaching it with an RFID reader that communicates with passive RFID tags deployed in the environment. One difficulty in RFID reader localization is that frequent RFID faults can affect localization accuracy. More specifically, in a complex localization environment, metal, water, obstacles, etc., causes some tags to fail to communicate with the reader, and consequently the localization result may deviate from the real location. For permanent faults, existing localization approaches can tolerate only faults that occur at individual tags, by utilizing the redundant information from their neighboring tags. However, these approaches cannot handle permanent faults that occur at a group of neighboring tags in a region, which is referred to as regional permanent fault. They will suffer from serious localization errors if such kind of faults occurs. Moreover, existing work lacks quality measurement of localization results, hence the user may be not aware how serious the localization errors can be. In this paper, we propose an effective fault-tolerant RFID reader localization approach that can handle regional permanent fault, and provide quality measurement of localization results. Our approach is applied to both 2D and 3D localization applications. We further study the network localization problem where some objects know their locations and the other objects determine their locations by measuring the distances to their neighbors. Using the localization results and especially the quality information obtained by our approach, we solve the network localization problem with improved localization accuracy. Evaluation results show that our approach outperforms existing approaches in localization accuracy and can provide additional useful quality information.