Research On Identification Protocol In Open RFID Systems

The National ”Thirteenth Five-Year Plan” proposes ”develop open-loop applications of the Internet of Things”,which is dedicated to promoting the interconnection,resource sharing and application collaboration between different industries and different fields of the Internet of Things.Radio Frequency IDentification(RFID)as one of the key supporting technologies of the Internet of Things,provides protection for the underlying perception of the Internet of Things.According to IDTech Ex statistics,the global RFID market in 2019 has reached 11.6 billion,and it is predicted to rise to 13 billion in 2022.With the increasing number of RFID devices and the expansion of application fields,the open RFID systems are becoming more common.Compared with traditional RFID systems,the open RFID systems have the characteristics of privacy sensitivity,uncertainty and large-scale,which brings unprecedented challenges to RFID identification.Focusing on the above three characteristics of the open RFID system,this thesis concentrates on the research on efficient tag identification by deactivating non-target tags and eliminating tag-tag collisions,so as to speed the management process of upperlayer applications.The main contributions of this thesis are summarized as follows:(1)For the privacy sensitivity of the open RFID systems,this thesis studies the problem of tag identification under blocker environment when we have the authorized reader(s).To protect the privacy,one widely used solution is to deploy one or more blocker tags to collide the RF signal sent from protected tags all the time.It is hard for the authorized reader to identify all genuine tags because of unreconciled collisions.In light of this,we propose three efficient tag identification protocols based on slot pairs and filtering technology.By silencing the known tags and establishing virtual and real response rules,we can identify the genuine tags in a time-efficient and privacyprotected way.(2)For the large-scale of the open RFID systems,this thesis studies how to let the readers concurrently identify tags.Due to limited communication range of one reader,it is common that the large-scale RFID systems deploy multiple readers to cover the whole monitor region.This thesis proposes a concurrent tag identification protocol.By solving the unbalanced reader load caused by uneven tag distribution and increase the number of useful slots,we can improve the tag identification throughput.(3)For the uncertainty of the open RFID systems,this thesis studies how to accurately identify all the missing tags by avoiding the interference of unexpected(nontarget)tags.To solve the misjudge caused by unexpected tags,this thesis proposes an order-based missing tag identification protocol that combines off line coding and online updating,which effectively solves the interference of unexpected tags while minimizing communication overhead.