Perfect tag identification protocol in RFID networks

Radio Frequency IDentification (RFID) systems are becoming more and more popular in the field of ubiquitous computing, in particular for objects identification. An RFID system is composed by one or more readers and a number of tags. One of the main issues in an RFID network is the fast and reliable identification of all tags in the reader range. The reader issues some queries, and tags properly answer. Then, the reader must identify the tags from such answers. This is crucial for most applications. Since the transmission medium is shared, the typical problem to be faced is a MAC-like one, i.e. to avoid or limit the number of tags transmission collisions. We propose a protocol which, under some assumptions about transmission techniques, always achieves a 100% perfomance. It is based on a proper recursive splitting of the concurrent tags sets, until all tags have been identified. The other approaches present in literature have performances of about 42% in the average at most. The counterpart is a more sophisticated hardware to be deployed in the manufacture of low cost tags.Comment: 12 pages, 1 figur

Tag Anti-collision Algorithm for RFID Systems with Minimum Overhead Information in the Identification Process

This paper describes a new tree based anti-collision algorithm for Radio Frequency Identification (RFID) systems. The proposed technique is based on fast parallel binary splitting (FPBS) technique. It follows a new identification path through the binary tree. The main advantage of the proposed protocol is the simple dialog between the reader and tags. It needs only one bit tag response followed by one bit reader reply (one-to-one bit dialog). The one bit reader response represents the collision report (0: collision; 1: no collision) of the tags' one bit message. The tag achieves self transmission control by dynamically updating its relative replying order due to the received collision report. The proposed algorithm minimizes the overhead transmitted bits per one tag identification. In the collision state, tags do modify their next replying order in the next bit level. Performed computer simulations have shown that the collision recovery scheme is very fast and simple even with the successive reading process. Moreover, the proposed algorithm outperforms most of the recent techniques in most cases

Towards Extended Bit Tracking for Scalable and Robust RFID Tag Identification Systems

The surge in demand for Internet of Things (IoT) systems and applications has motivated a paradigm shift in the development of viable radio frequency identification technology (RFID)-based solutions for ubiquitous real-Time monitoring and tracking. Bit tracking-based anti-collision algorithms have attracted considerable attention, recently, due to its positive impact on decreasing the identification time. We aim to extend bit tracking to work effectively over erroneous channels and scalable multi RFID readers systems. Towards this objective, we extend the bit tracking technique along two dimensions. First, we introduce and evaluate a type of bit errors that appears only in bit tracking-based anti-collision algorithms called false collided bit error in single reader RFID systems. A false collided bit error occurs when a reader perceives a bit sent by tag as an erroneous bit due to channel imperfection and not because of a physical collision. This phenomenon results in a significant increase in the identification delay. We introduce a novel, zero overhead algorithm called false collided bit error selective recovery tackling the error. There is a repetition gain in bit tracking-based anti-collision algorithms due to their nature, which can be utilized to detect and correct false collided bit errors without adding extra coding bits. Second, we extend bit tracking to 'error-free' scalable mutli-reader systems, while leaving the study of multi-readers tag identification over imperfect channels for future work. We propose the multi-reader RFID tag identification using bit tracking (MRTI-BT) algorithm which allows concurrent tag identification, by neighboring RFID readers, as opposed to time-consuming scheduling. MRTI-BT identifies tags exclusive to different RFIDs, concurrently. The concept of bit tracking and the proposed parallel identification property are leveraged to reduce the identification time compared to the state-of-The-Art. 2013 IEEE.This work was supported by the Qatar National Research Fund (a member of Qatar Foundation) through NPRP under Grant 7-684-1-127. The work of A. Fahim and T. ElBatt was supported by the Vodafone Egypt Foundation.Scopu

Energy aware improved least and most significant bit arbitration algorithm for WORM tags

AbstractPassive Radio Frequency Identification systems have gained enormous attention and popularity especially after its adoption in time and data critical systems. Theoretically, these systems have the potential to read over 100 tags per second in applications which are well insulated from RF noise. Nevertheless, this may not be the case in practical systems, as tag collision is one of the major deterrents affecting the recognition rate. This paper exhaustively analyses the existing probabilistic, deterministic and hybrid algorithms on collision resolutions. In probabilistic algorithms, tags send their entire ID to the RFID reader in respective slots while tags in deterministic algorithms respond bit by bit based on the RFID reader’s query. To minimize identification delay, tag communication overhead and high energy consumption, a new energy efficient collision resolution strategy named Improved Least and Most Significant Bit Algorithm (LaMSBA) is introduced to effectively singulate a tag and increase the identification efficiency in changing tag population even when the bits in tag ID’s are randomly or uniformly distributed. Extensive simulation studies show that LaMSBA can be chosen as better alternatives for dense time and data critical RFID enabled systems. In addition, M/G/1 Queuing model is suitably identified and the the analytical results concluded that LaMSBA is able to maintain the steady state condition even when Class 1 tags arrive at the rate of 15 tags/second in the reader’s interrogation zone

Fast splitting based tag identification algorithm for anti-collision in UHF RFID System

Efficient and effective objects identification using Radio Frequency Identification (RFID) is always a challenge in large scale industrial and commercial applications. Among existing solutions, the tree based splitting scheme has attracted increasing attention because of its high extendibility and feasibility. However, conventional tree splitting algorithms can only solve tag collision with counter value equals to zero and usually result in performance degradation when the number of tags is large. To overcome such drawbacks, we propose a novel tree-based method called Fast Splitting Algorithm based on Consecutive Slot Status detection (FSA-CSS), which includes a fast splitting (FS) mechanism and a shrink mechanism. Specifically, the FS mechanism is used to reduce collisions by increasing commands when the number of consecutive collision is above a threshold. Whereas the shrink mechanism is used to reduce extra idle slots introduced by FS. Simulation results supplemented by prototyping tests show that the proposed FSA-CSS achieves a system throughput of 0.41, outperforming the existing UHF RFID solutions

Energy efficient anti-collision algorithm for the RFID networks

Energy efficiency is crucial for radio frequency identification (RFID) systems as the readers are often battery operated. The main source of the energy wastage is the collision which happens when tags access the communication medium at the same time. Thus, an efficient anti-collision protocol could minimize the energy wastage and prolong the lifetime of the RFID systems. In this regard, EPCGlobal-Class1-Generation2 (EPC-C1G2) protocol is currently being used in the commercial RFID readers to provide fast tag identification through efficient collision arbitration using the Q algorithm. However, this protocol requires a lot of control message overheads for its operation. Thus, a reinforcement learning based anti-collision protocol (RL-DFSA) is proposed to provide better time system efficiency while being energy efficient through the minimization of control message overheads. The proposed RL-DFSA was evaluated through extensive simulations and compared with the variants of EPC-Class 1 Generation 2 algorithms that are currently being used in the commercial readers. The results show conclusively that the proposed RL-DFSA performs identically to the very efficient EPC-C1G2 protocol in terms of time system efficiency but readily outperforms the compared protocol in the number of control message overhead required for the operation

Persistent Q anti-collision algorithm for RFID

© Institution of Engineering and Technology.All Rights Reserved. In passive Radio Frequency Identification Systems (RFIDs), the interrogator should energise clients within range and use their backscattered replies to identify an inventory as quickly as possible. However, at the interrogator replies from two or more energised clients may collide and collided clients may not be identified. Therefore, collisions increase the number of timeslots needed to record an inventory. Reducing the number and frequency of collisions is an important and topical area research in RFID. Previously for passive Ultra High Frequency RFID the problem of collisions has been addressed using an ALOHA based protocol called the Q-Selection Algorithm. In this paper, a more efficient algorithm is presented that is shown to reduce the number of timeslots needed to record an inventory by approximately 30% when compared to the existing Q algorithm

Effect of slot type identification on frame length optimization

In dense radio frequency identification (RFID) systems, reducing reading times is crucial. For tag anti-collision management, most RFID systems rely on frame slotted ALOHA (FSA). The most common method to reduce the reading time for large tag populations is optimization of the number of slots per frame. The slot duration in real RFID systems is determined by the slot type (idle, successful, or colliding). Furthermore, by detecting the strongest transponder, colliding slots can be transformed to successful slots, a phenomenon known as the capture effect. Additionally, RFID readers might be capable of identifying slot types using the physical layer which reduces the colliding slot time because at this moment the reader can immediately terminate the connection as there is no need to reply with invalid acknowledge and wait for the time-out. In this paper, we provide a novel approach for analytical estimation of the optimal frame length. Our approach yields a novel closed form equation for the frame length that takes into account durations of different slot types, the capture effect, and the probability of slot type identification. Experimental results for FM0 encoding show that our technique achieves a total reading time reduction between 5.5% and 11.3% over methods that do not take into account slot type identification. However, the reduction in reading time is maximally 9%, 6%, and 1% for Miller encoding scheme with M = 2, 4, and 8, respectively

Tag anti-collision algorithms in RFID systems - a new trend

RFID is a wireless communication technology that provides automatic identification or tracking and data collection from any tagged object. Due to the shared communication channel between the reader and the tags during the identification process in RFID systems, many tags may communicate with the reader at the same time, which causes collisions. The problem of tag collision has to be addressed to have fast multiple tag identification process. There are two main approaches to the tag collision problem: ALOHA based algorithms and tree based algorithms. Although these methods reduce the collision and solve the problem to some extent, they are not fast and efficient enough in real applications. A new trend emerged recently which takes the advantages of both ALOHA and tree based approaches. This paper describes the process and performance of the tag anti-collision algorithms of the tree-ALOHA trend