Peter H. Cole

The reader collision problem in RFID systems

In a multi-reader environment, RFID system performance will be limited by the reader collision problem. RFID readers use different channels to minimise collision. However, with limited channels, the in-channel collision will happen. Using a path loss model, this paper predicts the safe distance between the readers before collisions occur in a same channel. This paper also explores the complication caused by the introduction of Listen Before Talk (LBT) in the European Regulation, makes suggestions on how reader collision problems and LBT effects can be minimised

Synchronization of RFID readers for dense RFID reader environments

For a dense RFID reader deployment, such as in warehouse RFID deployment, where hundreds of antennas are positioned in a building, the interference between all these readers must be studied carefully to avoid severe reader collisions. Strict RFID regulations and standards have been imposed, trying to address the problem of reader collision and also the problem of RFID devices interfering with other devices operating in nearby frequency bands. However, these guidelines and regulations are not entirely friendly for dense RFID reader deployment, in some cases it is not possible to have a feasible RFID system while adhering to these regulations. Hence, this paper proposes the synchronization of RFID readers, to enable successful dense RFID reader deployment. A case study targeted at European operations is presented in this paper to visualise the actual synchronization of RFID readers in real life applications. Some fine-tuning methods are also suggested to further improve the performance of readers in a high reader density population area

EPC Network Architecture

The concept of a “Networked Physical World” originated from the Auto-ID Center, now called the Auto-ID Labs [1]. Such a “World” can be realised with the combination of an automatic identification technology and a ubiquitous computer network that will glue the physical world together. Low cost RFID (Radio Frequency Identification) technology can automate identification of physical objects by providing an interface to link a vast number of objects to the digital domain. Thus, RFID as the enabling technology has paved the way forward for the creation of a “Networked Physical World”. The ability to form a ubiquitous item identification network has a wide range of applications including automation of manufacturing and supply chain management. The previous chapter provided a brief overview of RFID systems. This chapter describes the backend system components formulating a distributed ubiquitous item identification network enabled by the development of automatic identification provided by RFID technology, and examines the flow of tag data, once obtained by an interrogator. The implementation of such an architecture using a web services based model, as well as the impact of the network on supply chain applications, is also investigated.

Networked RFID Systems and Lightweight Cryptography

This book is a comprehensive guide to networks of Radio Frequency Identification (RFID) based Electronic Product Codes (EPCs) in supply chains, and its topics range from standardised hardware designs through known vulnerabilities, security and privacy models, and to concrete proposals for RFID authentication in various scenarios: machine readable documents, oneand two-way authentication in supply chains, and the pharmaceutical industry. Though a better insight into several discussion points requires additional reading, the book nevertheless provides both a good overview of the general challenges and opportunities in the area of supply chain RFID, and a comprehensive guide to further literature.

Operational considerations in simulation and deployment of RFID systems

Large-scale radio frequency identification (RFID) deployment is needed for efficient item identification in supply chains. To reduce cost and save time, simulations are often carried out before actual implementation, especially when RFID is used in regions in which strict regulations and standards must be adhered to. However, due to the unpredictable environmental effects on radio propagation simulation, simple results can be misleading and questions have been raised over the validity of many wireless simulations. This paper reviews, from the point of RFID antenna deployment, the sources of error in wireless simulations reported in some publications. Also, this paper offers important EMC information relevant to RFID system deployment

A small passive UHF RFID tag for livestock identification

RFID has its many applications, one use of this technology is for livestock identification. Animals such as cattle and sheep are tagged for purposes such as disease control, breeding management and also stock management. In this paper, a small passive RFID tag that can be attached to an animals ear and operating at UHF is presented. This paper covers the theoretical design including simulations and the practical implementation of this tag. Significant results obtained from simulations and laboratory testing of an animal ear tag are included in this paper.

Investigation of RF cable effect on RFID tag antenna impedance measurement

The performance of a passive radio frequency identification (RFID) tag depends on the antenna, the chip efficiency of the tag, and also on the matching between the antenna and the chip. The design of the tag antenna often involves the measurement of its impedance. There is no literature which explicitly discusses the measuring methods of the performance of an RFID tag antenna. The closest literature on the measurement of small antennas is either antenna on a mobile handset, mobile radio or antenna in a 50 Omega system. This paper investigates the RF cable effect on the measurement of the RFID tag antenna impedance. Measurement results obtained through several different RF cables are compared with simulation results. Discussions on minimizing measurement error and on how measurement of antenna impedance can assist the design of tag antenna are presented.

Security and privacy solutions for low-cost RFID systems

Low cost radio frequency identification (RFID) systems are increasingly being deployed in industry and commerce. These contactless devices have raised public concern regarding violation of privacy and information security. There is a growing need in the RFID community to discover and develop techniques and methods to overcome several problems posed by the abovementioned concerns. This paper presents proposals on feasible security mechanisms for low cost RFID systems and analyses them from both security and privacy points of view.

Analysis of infinite arrays of substrate-supported metal strip antennas

An electric field integral equation method is applied to a metal strip antenna on an electrically thick dielectric substrate of finite size in a uniform infinite array environment. An efficient solution is found using the method of moments. Metal strip folded dipole antennas are analyzed both with and without a coplanar strip feed line, and the effects of the substrate and feed line are investigated. A technique for minimizing the effect of feed line scattering is presented, and arrays of these elements are shown to be capable of good scanning performance over a wide range of beam-steer angles. A phased array simulator experiment is described and the measured results show good agreement with those obtained by analysis. The class of antenna elements studied may be fabricated using monolithic microwave integrated circuit (MMIC) technology, and the analysis described illustrates the expected characteristics for millimeter-wavelength phased arrays of this type. >

Confronting Security and Privacy Threats in Modern RFID Systems

The modern form of RFID technology that is set to dominate is that enabled by low cost RFID technology. This paper presents an overview of the technological aspects vital to illuminating associated security and privacy threats The paper also describes a simple security model and briefly considers some of the vulnerabilities faced by such low cost RFID systems. Finally the authors would like to extend preliminary work published on a minimalist encryption method first published in [26] and [27].