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

Goodbye, ALOHA!

©2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The vision of the Internet of Things (IoT) to interconnect and Internet-connect everyday people, objects, and machines poses new challenges in the design of wireless communication networks. The design of medium access control (MAC) protocols has been traditionally an intense area of research due to their high impact on the overall performance of wireless communications. The majority of research activities in this field deal with different variations of protocols somehow based on ALOHA, either with or without listen before talk, i.e., carrier sensing multiple access. These protocols operate well under low traffic loads and low number of simultaneous devices. However, they suffer from congestion as the traffic load and the number of devices increase. For this reason, unless revisited, the MAC layer can become a bottleneck for the success of the IoT. In this paper, we provide an overview of the existing MAC solutions for the IoT, describing current limitations and envisioned challenges for the near future. Motivated by those, we identify a family of simple algorithms based on distributed queueing (DQ), which can operate for an infinite number of devices generating any traffic load and pattern. A description of the DQ mechanism is provided and most relevant existing studies of DQ applied in different scenarios are described in this paper. In addition, we provide a novel performance evaluation of DQ when applied for the IoT. Finally, a description of the very first demo of DQ for its use in the IoT is also included in this paper.Peer ReviewedPostprint (author's final draft

New tag estimator for the dynamic framed slotted Aloha anti-collision algorithm in RFID systems

Radio frequency identification (RFID) technology is a wireless identification technique that has been used in many fields. This paper investigates the use of this technology for traffic monitoring which is the backbone of any intelligent transportation system. One of the main issues that face this technology is tag collisions. This study examines the performance of two known anti-collisions protocols: the Basic Framed Slotted Aloha (BFSA) and the Dynamic Framed Slotted Aloha (DFSA). For such application, it was found that the DFSA method outperforms the BFSA method. However, the DFSA method requires the use of tag estimator. For this reason, the study compares also the performance of three tag estimators associated with the DFSA: Vogt, Zhen and Schoute. It is observed that the Vogt method is the best if the number of tags is low, while the Schoute approach is superior for higher value. The study proposes a new hybrid tag estimator that combines the strength of the Vogt and Schoute approaches

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

A fast tag identification anti-collision algorithm for RFID systems

© 2019 John Wiley & Sons, Ltd. In this work, we propose a highly efficient binary tree-based anti-collision algorithm for radio frequency identification (RFID) tag identification. The proposed binary splitting modified dynamic tree (BS-MDT) algorithm employs a binary splitting tree to achieve accurate tag estimation and a modified dynamic tree algorithm for rapid tag identification. We mathematically evaluate the performance of the BS-MDT algorithm in terms of the system efficiency and the time system efficiency based on the ISO/IEC 18000-6 Type B standard. The derived mathematical model is validated using computer simulations. Numerical results show that the proposed BS-MDT algorithm can provide the system efficiency of 46% and time system efficiency of 74%, outperforming all other well-performed algorithms

Frame Size Analysis of Optimum Dynamic Tree in RFID Systems

In RFID (Radio Frequency Identification) system, an anti-collision algorithm plays a prominent role in the tag identification process in order to reduce the tag identification delay and enhance the RFID system efficiency. In this work, we present a theoretical analysis of optimal frame size assignment for maximizing the system efficiency of a tree-based anti-collision algorithm, called optimum dynamic tree (ODT) algorithm, for RFID tag identification process. Our analysis indicates that the appropriate frame size for a given number of competing tags should not be set to the same value as the number of tags, which is commonly adopted in the literature. Instead, the frame size should be smaller roughly by a factor of 0.871 to maximize system efficiency. The closed-form for calculating system efficiency is derived and the derived simulation results are in a good agreement with the theoretical one. The exact appropriate frame sizes for the number of tags ranging from 2 to 100 are tabulated and compare the tag-identification time of conventional binary tree and ODT algorithms by using the international standard ISO 18000-6B

Improved RFID Anti-collision Protocol for EPCglobal Class-1 Generation-2

One of the important feature in the RFID technology is its functionality without needs to line of sight which makes it more feasible than other similar technologies. The problem occurs when more than one tag reply to the reader at the same time and collide together. To resolve the mentioned issue an anti-collision algorithm has to be used. The anti-collision algorithms are mostly efficient if the number of tags are small and has not been designed for large number of tags. In some applications that the number of tags may be hundreds of tags the existing mechanism may reduce the performance of the system due to delayed algorithms. In this paper an improved anti-collision protocol has been proposed. A modified two-parameter step size method for Q algorithm is also used to increase the efficiency of reading. The step sizes are adjusted depending on collisions in previous round. The number of slots in each round is also adjusted to prevent collisions in next rounds. The performance of proposed protocol has been evaluated using RFID module that implements EPCglobal C1G2 and designed especially for IoT environment and find the proposed protocol effective. Keywords: RFID, Anti-collision, EPCglobal, Q algorithm, DFSA

Analysis of BFSA Based Anti-Collision Protocol in LF, HF, and UHF RFID Environments

Over the years, RFID (radio frequency identification) technology has gained popularity in a number of applications. The decreased cost of hardware components along with the recognition and implementation of international RFID standards have led to the rise of this technology. One of the major factors associated with the implementation of RFID infrastructure is the cost of tags. Low frequency (LF) RFID tags are widely used because they are the least expensive. The drawbacks of LF RFID tags include low data rate and low range. Most studies that have been carried out focus on one frequency band only. This thesis presents an analysis of RFID tags across low frequency (LF), high frequency (HF), and ultra-high frequency (UHF) environments. Analysis was carried out using a simulation model created using OPNET Modeler 17. The simulation model is based on the Basic Frame Slotted ALOHA (BFSA) protocol for non-unique tags. As this is a theoretical study, environmental disturbances have been assumed to be null. The total census delay and the network throughput have been measure for tags ranging from 0 to 1500 for each environment. A statistical analysis has been conducted in order to compare the results obtained for the three different sets