Preface ix

Chapter 1 Introduction to Chipless Radio Frequency Identification 1

1.1 Introduction 1

1.2 Chipless radio frequency identification 1

1.3 Recent developments and advancements 4

1.4 Authentication 14

1.5 Conclusion 15

Chapter 2 Literature Review 17

2.1 Introduction 17

2.2 State of the art 18

2.2.1 Basic level of security (overt or visible features) 20

2.2.2 Medium level of security (covert or hidden markers) 22

2.2.3 High level of security (forensic techniques) 23

2.2.4 Conventional RFID approaches 24

2.2.5 Classical chipless approaches 27

2.2.6 Natural randomness 28

2.3 Conclusion 30

Chapter 3 Methodology and Proof of Concept 31

3.1 Introduction 31

3.2 Randomness inherent in the realization process 32

3.3 Authentication procedure 34

3.4 Statistical analysis 37

3.5 Chipless tag discrimination using PCB tags 39

3.5.1 Chipless tag design and purposely applied dimensional variations 40

3.5.2 Chipless tag discrimination results and performance of the resemblance metrics 44

3.6 Chipless tag discrimination using inkjet-printed paper tags 47

3.6.1 Chipless tag design and purposely applied dimensional variations 47

3.6.2 Chipless tag discrimination results and performance of the resemblance metrics 48

3.7 Conclusion 51

Chapter 4 Extraction of Chipless Tag Key Parameters from Backscattered Signals 53

4.1 Introduction 53

4.2 Chipless RFID tags and measurement setup 57

4.3 Extraction of aspect-independent parameters of a second-order scatterer 61

4.3.1 Extraction with the matrix pencil method 64

4.3.2 Extraction with the spectrogram method 67

4.4 Extraction of CNRs of the multi-scatterer-based tags 73

4.5 Comparison of computational time durations between the matrix pencil method and the spectrogram method 82

4.6 Conclusion 83

Chapter 5 Chipless Authentication Using PCB Tags 85

5.1 Introduction 85

5.2 Design and the optimization of chipless tags to be employed for authentication 86

5.2.1 C-folded uni-scatterer tags (classical design) 87

5.2.2 C-folded quad-scatterer tags (optimized design) 94

5.3 Detection of minimum dimensional variation in outdoor realistic environment and authentication results 100

5.4 Detection of natural randomness and authentication results 106

5.4.1 Authentication within each realization 108

5.4.2 Authentication across different realizations 111

5.4.3 Characterization of the natural randomness 112

5.4.4 Generalization of the proposed method 117

5.4.5 Final remarks on the constraints 118

5.5 Conclusion 119

Chapter 6 Chipless Authentication Using Inkjet-Printed PET Tags 121

6.1 Introduction 121

6.2 Optimization of chipless tags to exploit natural randomness inherent in inkjet printing 122

6.3 Authentication using VNA-based chipless reader 129

6.4 Authentication using IR-UWB chipless reader 136

6.5 Conclusion 142

Conclusion 145

Appendices 149

Appendix A 151

Appendix B 153

Appendix C 155

References 157

Index 173