Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
An Analytical Model for Electro-magnetically Coupled UHF RFID Sensor Tags
Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.ORCID iD: 0000-0002-3790-0729
2013 (English)In: 2013 IEEE INTERNATIONAL CONFERENCE ON RFID (RFID), IEEE conference proceedings, 2013, p. 66-73Conference paper, Published paper (Refereed)
Abstract [en]

This paper presents an analytical model for electromagnetically coupled UHF RFID sensor tags where a coupling loop with an embedded sensor is attached to an ordinary UHF RFID tag with a small gap. Electromagnetic coupling is used, in this case, to modulate the properties of the tag antenna in proportion to the values of the embedded sensor. The antenna together with the coupling loop are represented as an equivalent circuit and the analysis of the sensor tag becomes a circuit-level calculation after extracting parameters from full-wave simulations for, respectively, the separated dipole antenna and coupling loop. The results calculated from the equivalent circuit model are compared with the results from full-wave simulations and show good agreement. The presented model can thus be used for analyzing and predicting the behavior of electromagnetically coupled sensor tags. Based on the analysis with the presented model, the methods for optimizing the sensory performance of this kind of RFID sensor tags are also presented in this paper.

Place, publisher, year, edition, pages
IEEE conference proceedings, 2013. p. 66-73
National Category
Embedded Systems
Identifiers
URN: urn:nbn:se:miun:diva-19571ISI: 000326738900010Scopus ID: 2-s2.0-84881346251Local ID: STCISBN: 978-1-4673-5750-0 (print)ISBN: 978-1-4673-5748-7 (print)OAI: oai:DiVA.org:miun-19571DiVA, id: diva2:636383
Conference
IEEE International Conference on RFID (RFID, Orlando, FL, Apr 30-May 02 2013
Available from: 2013-07-09 Created: 2013-07-09 Last updated: 2016-10-19Bibliographically approved
In thesis
1. Antenna-based passive UHF RFID sensor tags: Design and application
Open this publication in new window or tab >>Antenna-based passive UHF RFID sensor tags: Design and application
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

RFID, as a low cost technology with a long life time, provides great potential for transmitting sensor data in combination with the ordinary ID number. The sensor can, for example, be integrated either in the chip or in the antenna of an RFID tag.This thesis focuses on the design of antenna-based UHF RFID sensor tags as wireless sensors at the lowest possible cost level compatible with standard communication systems in logistics. The applications of the sensor tags, in this work, mainly target remote humidity sensing. Antenna-based sensory UHF RFID tags utilize the influence that the physical or chemical parameters to be sensed have on the electrical properties of a tag antenna. The variations of the electrical properties of the tag antenna can be measured in many ways. In the thesis, a description is provided as to how these variations are normally measured by an RFID reader without any other assistant equipment. Three structures of antenna-based RFID sensor tags are presented with detailed characterizations. The first one utilizes the sensitivity of the antenna to the surrounding environment to construct RFID sensor tags, where a moisture absorbing layer providing wetness/humidity sensor functionality is placed on the RFID tag antenna to increase the humidity concentration surrounding the tag antenna and the thesis describes how to overcome certain limitations due to disturbances associated with background materials. The second structure directly integrates a small resistive sensor element into an RFID tag antenna and the sensor information can thus modulate the antenna performance by means of galvanic contact. The third structure embeds a small resistive sensor element into a loop which is positioned on top of the tag antenna and the sensor information can thus modulate the performance of the tag antenna by means of electromagnetic coupling. Both theoretical analysis and fullwave simulations are presented for the latter two sensor tag structures in order to characterize the performance of the sensor tags. An ultra-low cost printed humidity sensor with memory functionality is also designed and thoroughly characterized for integration into RFID tag antennas by means of galvanic contact or electromagnetic coupling. The sensor is a 1-bit write-once-read-many (WORM) memory printed using conductive ink. The WORM works as a pure resistive humidity sensor and can provide information about an historical event. The WORM sensor is presented by introducing its geometry, characterizingits behavior in humidity and explaining the principle of the humidity effect. The WORM sensors are also integrated into the RFID tags by means of both galvanic contact and electromagnetic coupling in order to experimentally verify the two concepts. To lower the cost of the RFID tags, the antennas are normally printed, milledor etched on flexible substrates using low-cost high-speed manufacturing methods which in some cases cause a high degree of edge roughness. The edge roughness will affect the behavior of the antenna, however, the characteristics of edge roughness on RFID antennas have previously not received any significant attention. Unforeseen antenna behavior can affect the antenna-based sensor tags, thus the influence of edge roughness is also investigated in the thesis.

Place, publisher, year, edition, pages
Sundsvall: Mid Sweden University, 2013. p. 84
Series
Mid Sweden University doctoral thesis, ISSN 1652-893X ; 157
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:miun:diva-19889 (URN)STC (Local ID)978-91-87103-99-5 (ISBN)STC (Archive number)STC (OAI)
Public defence
2013-06-18, Sundsvall, 13:15 (English)
Opponent
Supervisors
Available from: 2013-09-19 Created: 2013-09-19 Last updated: 2016-10-19Bibliographically approved

Open Access in DiVA

No full text in DiVA

Scopus

Search in DiVA

By author/editor
Gao, JinlanSidén, JohanNilsson, Hans-Erik
By organisation
Department of Electronics Design
Embedded Systems

Search outside of DiVA

GoogleGoogle Scholar

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 573 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf