Missing Tag Detection Protocols Research Articles

A High Time-Efficient Missing Tag Detection Scheme for Integrated RFID Systems.

Missing tag incidents are common in RFID-enabled supply-chain and warehousing scenarios due to cargo theft and employee error operations, which may lead to serious economic losses or potential safety hazards. On the premise of ensuring the accuracy of missing tag detection, this paper aims to improve the time efficiency in an integrated RFID system. Unlike prior work focusing on detecting missing items from a large number of homogeneous tags that are monitored by a single reader, one integrated RFID system possesses multiple readers to communicate with the heterogeneous tags, which have different categorical attributes. In addition, the prior work required repeating the execution several times to capture the missing tags in assorted categories, which is of low time efficiency. Thus, a protocol called Multi-reader Missing Tag Detection (MMTD) is proposed to capture the missing tag quickly and reliably, which can detect missing tags from different categories in a parallel manner and is much more time-efficient than previous work. MMTD has two major advantages compared to prior work: (i) It leverages the knowledge of the spatial distribution of tags to divide up a difficult detection task into several lightweight tasks, which are shared by multiple readers. (ii) It personalizes the time frame of the reader based on the tag population to optimize the utilization of the communication channel. The final simulation results reveal that MMTD is the best in time-efficiency among the comparison protocols, and MMTD outperforms the other missing tag detection protocols by at least in the Integrated RFID scenarios.

Fast and Reliable Missing Tag Detection for Multiple-Group RFID Systems

Radio frequency identification (RFID) technology has been deployed in various scenarios in recent years. In some practical RFID applications, the items attached with tags can be divided into multiple groups. Thus, the efficient and accurate missing tag detection of each group is critical. Accordingly, this article concentrates on the problem of missing tag detection in the multiple-group RFID systems, after which three distinctive protocols are proposed. First, we propose an aptitudinal multiple-group missing tag detection protocol, which makes full use of the expected singleton slots. Then, an enhanced multiple-group missing tag detection protocol is proposed, which can achieve significant broadcast and response savings. Finally, an accurate and expeditious multiple-group missing tag detection protocol is designed, the detection reliability of which can approximate 100%. The theoretical analysis and extensive simulations are conducted and the results verify that the proposed protocols in this article outperform the other ones.

Missing-Tag Detection With Unknown Tags

Radio Frequency Identification (RFID) technology has been proliferating in recent years, especially with its wide usage in retail, warehouse and supply chain management. One of its most popular applications is to automatically detect missing products (attached with RFID tags) in a large storage place. However, most existing protocols assume that the IDs of all tags within a reader’s coverage are known, while ignoring practical scenarios where the IDs of some tags may be unknown. The existence of these unknown tags will introduce false positives in those protocols, degrading their performance. Some prior art studies this problem, but their time efficiency is low, especially when the number of unknown tags is large. In this paper, we propose a new missing tag detection protocol based on compressed filters, which not only reduce the filter size for better time-efficiency but also help dampen the interference of unknown tags for high missing-tag detection accuracy. To further improve the performance, we propose to use a combination of sampling and multi-hashing for tags to report their presence, greatly reducing collisions and thus improving the detection probability. We reconfigure the standard ID collection protocol to support bitmap collection required by missing-tag detection. Extensive simulations demonstrate that our compressed filter and collision-reduction method reduce the protocol execution time by 83% to 92% under the same missing-tag detection probability, when comparing with the best prior work. We also evaluate the performance of our missing-tag detection protocol under unreliable channel.

EUMD: Efficient slot utilization based missing tag detection with unknown tags

Radio frequency identification (RFID) technology, which obtained significant development in the past several decades, is widely applied in numerous industrial applications. One of the typical applications is to detect the missing tags, which can perform real-time detection of missing objects while each object is attached with a low-cost RFID tag in a large-scale warehouse. However, there actually may be a large number of unknown tags whose IDs are not known by reader to disturb the missing tag detection. The existence of unknown tags not only reduces the detection efficiency but also affects the detection reliability. Unfortunately, some existing missing tag detection protocols fail to deal with the interferences of unknown tags well. In this paper, we propose an efficient and reliable scheme called EUMD which consists of two phases to detect the missing tags. In particular, EUMD introduces the grid table to improve the ratio of empty slots to enhance the deactivation efficiency in the first phase. In the second phase, Hash function based on ID shifting is deployed to improve the utilization of singleton slots. After that, extensive simulations are conducted, which demonstrate that the execution efficiency of EUMD scheme can be increased at least by 20% compared with the exiting protocol.

On Missing Tag Detection in Multiple-Group Multiple-Region RFID Systems

We formulate and study a missing tag detection problem arising in multiple-group, multiple-region radio frequency identification (RFID) systems, where a mobile reader needs to detect whether there is any missing event for each group of tags. The problem we tackle is to devise missing tag detection protocols with minimum execution time while guaranteeing the detection reliability requirement for each group. By leveraging the technique of Bloom filter, we develop a suite of three missing tag detection protocols, each decreasing the execution time compared to its predecessor by incorporating an improved version of the Bloom filter design and parameter tuning. By sequentially analyzing the developed protocols, we gradually iron out an optimum detection protocol that works in practice.

Finding Needles in a Haystack: Missing Tag Detection in Large RFID Systems

Radio frequency identification technology has been widely used in missing tag detection to reduce and avoid inventory shrinkage. In this application, promptly finding out the missing event is of paramount importance. However, the existing missing tag detection protocols cannot efficiently handle the presence of a large number of unexpected tags whose IDs are not known to the reader, which shackles the time efficiency. To deal with the problem of detecting missing tags in the presence of unexpected tags, this paper introduces a two-phase Bloom filter-based missing tag detection (BMTD) protocol. The proposed BMTD exploits Bloom filter in sequence to first deactivate the unexpected tags and then test the membership of the expected tags, thus dampening the interference from the unexpected tags and considerably reducing the detection time. Moreover, the theoretical analysis of the protocol parameters is performed to minimize the detection time of the proposed BMTD and achieve the required reliability simultaneously. In addition, we derive a critical threshold on the unexpected tag size for the execution of first phase in BMTD. Extensive experiments are then conducted to evaluate the performance of the proposed BMTD. The results demonstrate that the proposed BMTD significantly outperforms the state-of-the-art solutions.