RFID at Ultra and Super High Frequencies: Theory and application

Preface.

Acknowledgements.

Note to Readers.

Part One RFID: General Features, Basic Principles and Market.

1 Introduction, Definitions and Vocabulary.

1.1 To Understand Radio Frequency, We Must Know about Frequencies and Their Classification.

1.2 RFID: Who Uses It and What For?

1.3 History.

1.4 Radio Frequency (or Contactless) Identification and Its Range of Applications.

1.5 The Concept of Contactless Communication.

1.6 The Elements, Terms and Vocabulary of RFID.

1.7 Vocabulary: The Many Terms Used for the Elements Of RFID.

1.8 Appendix: Units and Constants.

2 General Operating Principles of the Base Station-Tag Pair.

2.1 Energy Transfer and Communication Modes.

2.2 Forward Link and Return Link.

2.3 Data Communications.

2.4 The Principle of Communication.

2.5 The Concept of Operating Modes.

2.6 General Operating Problems in Data Transmission.

2.7 More Specific Problems Relating to ‘Long Distance’ RFID Systems.

3 The Market and Applications for Contactless Technology.

3.1 The Market for Contactless Technology and RFID.

3.2 Applications for Tags.

3.3 Operators and Participants in the Market.

Part Two Wave Propagation: Principles, Theories ... and the Reality.

4 Some Essential Theory.

4.1 The Phenomenon of Propagation and Radiation.

4.2 The Hertzian Dipole.

4.3 Classification of Fields and Regions of Space.

4.4 RFID Applications Using UHF and SHF, i.e. Far Field Applications.

4.5 The Hertzian Dipole and the Dipole of any Length, λ/n and λ/2.

4.6 List of the Main Formulae in This Chapter.

4.7 Appendix 1: Brief Notes on Maxwell’s Equations.

4.8 Appendix 2: Brief Notes on Complex Numbers.

4.9 Appendix 3: Brief Notes on Powers Expressed as Complex Numbers.

4.10 Appendix 4: Brief Notes on Vectors.

5 Wave Propagation in Free Space.

5.1 Isotropic and Anisotropic Antennas.

5.2 Antenna Gain.

5.3 Power Flux Density at One Point in Space.

5.4 Effective Radiated Power PERP.

6 Power Recovery at the Terminals of the Tag Antenna.

6.1 Recovering the Transmitted Radiated Power (or Some of It).

6.2 The Concept of Aperture or Surface.

6.3 Definition of the Main Parameters Required for an RFID Application.

7 Reality Check: How to Manage Everyday Problems.

7.1 Effects of the Application Environment.

7.2 Tag Polarization Losses, θ polarization = P.

7.3 Antenna Load Mismatch Factor, θ load matching = q.

7.4 Voltage Standing Wave Ratio (VSWR).

7.5 Losses Due to the Physical Design of the Antenna, θantenna.

7.6 By Way of Conclusion.

7.7 Real-World Examples of RFID at UHF and 2.45 GHz.

7.8 Effects of the Mounting of the Integrated Circuit on the Tag Substrate.

7.9 By Way of Conclusion.

7.10 Example at UHF and SHF.

7.11 Appendix: Fact and Fantasy about UHF Tags and Water.

8 Reflection and/or Reradiation of Waves and RFID Applications.

8.1 The Physical Phenomenon of Wave Scattering.

8.2 Scattering Modes.

8.3 Power Dispersed/Reradiated/Reflected by the Tag, Ps.

8.4 Radar Cross-Section (RCS) of the Tag, σ e s.

8.5 Appendix.

9 The Back Scattering Technique and Its Application.

9.1 The Principle of Communication by Back Scattering between the Base Station and the Tag.

9.2 The Merit Factor of a Tag, Δσe s or ΔRCS.

9 3 Appendix: Summary of the Principal Formulae of Chapters 7, 8 and 9.

10 RFID Case Studies Summarizing the Preceding Chapters.

10.1 Case 1: Application to a ‘Remotely Powered Passive Tag’.

10.2 Case 2: Application to a ‘Battery-Assisted Passive Tag’.

10.3 Examples 1a and B: Application to a ‘Remotely Powered Passive Tag’.

10.4 Example 2: Application to a ‘Battery-Assisted Passive Tag’.

Part Three Communication and Transmission, Baseband Signals, Carrier Modulation and Interleaving.

11 Digital Aspect: Bit Coding and Baseband Signals.

11.1 Bit Coding.

11.2 Different Types of Bit Coding for use in RFID at UHF and SHF.

11.3 Summary of the Different Types of Bit Coding.

12 Analogue Aspect: Carrier Modulation Methods.

12.1 Type of Modulation.

12.2 Types of Carrier Modulation for the Forward Link from the Base Station to the Tag.

12.3 Amplitude Modulation.

12.4 Frequency Modulation and Phase Modulation.

12.5 Conclusion.

13 Spread Spectrum Techniques.

13.1 Frequency Hopping and Agility Systems and Spread Spectrum Techniques.

13.2 Spread Spectrum Techniques (Spread Spectrum Modulation, SS).

13.3 Frequency Hopping or Agility Systems for Spreading the Radiated Spectrum of Narrowband Modulated Carriers.

13.4 Spread Spectrum Systems for Spreading the Radiated Spectrum of Wide Band Modulated Carriers.

13.5 ‘Hybrid’ Spread Spectrum Techniques: DSSS and FHSS.

13.6 Back to the Future.

13.7 Examples at SHF.

13.8 FHSS, LBT, DSSS ... and RFID.

14 Interactions and Conclusion.

14.1 Relations, Interactions and Performance: How They Are Affected by the Choice of Bit Coding and the Types of Modulation Used.

14.2 General Conclusion of Part Three.

Part Four Standards and Regulations.

15 Standards for RFID at UHF and SHF.

15.1 The Purpose of the Standards.

15.2 Users and Providers of Standards.

15.3 The ISO/OSI Layer Models.

15.4 ISO Standards for Contactless Technology.

15.5 Appendix 1: Hierarchy and Structure of the EPC System.

15.6 Appendix 2: The Structure of the EPC Number.

15.7 Appendix 3: Some Facts about the Everyday Performance of ISO 18000-6 mode C – EPC C1 G2.

16 Regulations and Human Exposure.

16.1 Survey of Standards and Regulations.

16.2 Summary of Regulations in the USA, Europe, France and the Rest of the World Relating to RFID at UHF and SHF.

16.3 Standards for Magnetic and Electrical Fields in a Human Environment: Human Exposure.

16.4 Other Requirements to be Met.

16.5 Appendix.

17 The Effects and Repercussions of Regulations on Performance.

17.1 Frequencies.

17.2 Transmission Level.

17.3 Summary.

17.4 Comparison between Europe and the USA.

17.5 UHF or 13.56 MHz Around the World and in Europe.

17.6 Appendix: The Main Standards and Regulations.

Part Five Components for Tags and Base Stations.

18 RFID Tags.

18.1 Some General Remarks.

18.2 Summary of Operating Principles.

18.3 The Technology of Tags.

18.4 Antennas for Tags.

19 The Base Station.

19.1 Introduction.

19.2 Examples of Base Station Hardware Architecture.

19.3 Examples of Products.

19.4 Antennas for Base Stations.

19.5 Some Concluding Remarks.

20 Conformity, Performance and Methods for Evaluating Tags and Systems.

20.1 Official Measurement and Test Methods.

20.2 Required Parameters.

20.3 Simple Methods of Measurement.

20.4 By Way of Conclusion.

Conclusions.

Useful Addresses, Component Manufacturers and Further Reading.

Index.