Passive RFID Localization Research Articles

Underground Passive LF RFID Localization Method Based on Magnetic Field Model of Reader Coil Antenna

Underground Passive LF RFID Localization Method Based on Magnetic Field Model of Reader Coil Antenna

A Novel Integrated UWB–UHF One-Port Antenna for Localization and Energy Harvesting

In this work, a novel, compact, single-port antenna combining both UWB and UHF bands is presented. This solution is proposed for next-generation passive RFID tags, performing communication and localization through UWB technology and efficient energy harvesting in the UHF band, but it is also designed to keep compatibility with previous tags generations. The UWB communication is deployed by means of an Archimedean spiral topology, while energy harvesting at UHF is obtained by suitably extending the spiral outer arms, thus realizing a meandered dipole, without affecting the UWB behavior. The single-port architecture provides an overall size reduction, while preserving the radiation performance in both the operating bands. This solution allows a direct connection to future integrated UWB-UHF chips, to standard RFID chips, or to a diplexer for suitably combining the UWB and the UHF functionalities. A prototype of this new antenna, realized on a standard FR-4 substrate, is first presented to validate the proposed novel design. As a second step, the same architecture is scaled on a paper substrate in view of its fully eco-compatible realization to be exploited by future pervasive RFID applications. The compact design of the antenna-feeding network in discrete technology is also presented.

Accurate RFID Trilateration to Learn and Recognize Spatial Activities in Smart Environment

The rapid adoption of wireless communication and sensors technology has raised the awareness of many laboratories about the field of network embedded system. Most researchers aim to exploit these advances to enable technological assistance of frail persons in smart homes. However, to reach the full potential of applications using network embedded systems such as assistive smart home, scientists need to work toward the creation of support services. In this paper, we present an accurate passive RFID localization technique, which can easily be implemented and deployed in various environments, coupled to a complete human activity recognition model. The goal of this paper is to demonstrate, through concrete experiments, that support services can enable powerful solution to long-lived challenges of the network embedded system community. Particularly, the model exploits qualitative spatial reasoning from RFID localization of objects in the smart home to learn and recognize the basic and instrumental activities of daily living of a resident. Our system was deployed in a real smart home, and the results obtained were quite encouraging. The developed RFID technique gives an average precision of ±14.12 cm, and the recognition algorithm recognizes up to 92% activities.

수동 RFID 기반 이동로봇 위치 추정 및 효율적 노면 태그 배치

Under passive RFID environment, this paper presents a new localization of a mobile robot traversing over the floor covered with tags, which is superior to existing methods in terms of estimation performance and cost effectiveness. Basically, it is assumed that a mobile robot is traveling along a series of straight line segments, each segment at a certain constant velocity, and that the number of tags sensed by a mobile robot at each sampling instant is at most one. First, for a given line segment with known starting point, the velocity and position of a mobile robot is estimated using the spatial and temporal information acquired from the traversed tag. Some discussions are made on the validity of the basic assumptions and the localization for the initial segment with unknown starting point. Second, for a given tag distribution density, the optimal tag arrangement is considered to reduce the position estimation error as well as to make easy the tag attachment on the floor. After reviewing typical tag arrangements, the pseudorandom tag arrangement is devised inspired from the Sudoku puzzle, a number placement puzzle. Third, through experiments using our passive RFID localization system, the validity and performance of the mobile robot localization proposed in this paper is demonstrated.