A protocol for detecting missing target tags in RFID systems

Radio Frequency IDentification (RFID) technology is widely used in the inventory management of goods. Fast searching a subset consisting of some particular target tags is of practical importance for a variety of applications. Existing protocols are inefficient due to the low utilization of frame. In this paper, in order to improve the utilization of slot frame, we first generalize Cuckoo hash to extended Cuckoo hash which can use more than two hash functions. Then, we propose an extended CUckoo hash-based missing tag Detection (CUD) protocol, which can efficiently identify all missing tags within a predefined specific set. In CUD, the reader first uses the extended cuckoo hash to generate a fingerprint vector of the target tags. By using this vector, almost all target tags can be assigned a single slot and the majority of non-target tags can be filtered out. Furthermore, we optimize the parameters through theoretical analysis to minimize the execution time of the protocol. Extensive simulation results demonstrate that CUD is superior to the state-of-the-art protocols.