Antennas, Waves, and Circuits in Radio Frequency - Auto-ID Lab

217 Pages·2011·3.07 MB·English

Antennas, Waves, and Circuits
in
Radio Frequency Identi(cid:12)cation
David M. Hall
A thesis submitted for the degree of
Doctor of Philosophy
in
Electrical and Electronic Engineering
The University of Adelaide
September 2011
“Alltruthsareeasytounderstandoncetheyarediscovered
–thepointistodiscoverthem.”
GalileoGalilei(1564-1642).
Contents
Abstract viii
Statement of Originality ix
Acknowledgments x
Conventions xi
Publications of the Author xii
Abbreviations xiv
List of Figures xvii
List of Tables xxii
Chapter 1. Introduction 1
1.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.2 Outlineofthethesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.3 Originalcontributionsoftheauthor . . . . . . . . . . . . . . . . . . 4
Chapter 2. UHF Planar Tags 6
2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2 Readrange . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.3 RFIDantennaimpedance . . . . . . . . . . . . . . . . . . . . . . . . 7
2.4 Calibratingthesimulator . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.4.1 TheBalanisdipoleanalysis . . . . . . . . . . . . . . . . . . . 11
2.4.2 Losscalculationofahalf-wavedipole . . . . . . . . . . . . . 13
2.5 Shorteningtheantenna . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.6 Dipolewithaloop . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.6.1 Modellingabook . . . . . . . . . . . . . . . . . . . . . . . . . 21
2.7 Close-coupledtags . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
2.8 Atwo-porttag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
2.9 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
iii
Contents iv
Chapter 3. A Two-Part UHF Antenna 35
3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
3.2 Partsofthetag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
3.2.1 Theprimaryantenna . . . . . . . . . . . . . . . . . . . . . . . 37
3.2.2 Thesecondaryantenna . . . . . . . . . . . . . . . . . . . . . 38
3.2.3 Thecompletedtag . . . . . . . . . . . . . . . . . . . . . . . . 39
3.3 Tagtesting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
3.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Chapter 4. A Combined UHF and HF Antenna 47
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
4.2 Animproveddesign . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
4.3 UHFlayer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
4.4 HFlayer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
4.5 CombinedUHFandHFlayers . . . . . . . . . . . . . . . . . . . . . 50
4.6 RFIDloop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
4.7 Thecompletetag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
4.8 RFIDoperationoftheHFfeature . . . . . . . . . . . . . . . . . . . . 54
4.9 RFIDloopontheUHFlayer . . . . . . . . . . . . . . . . . . . . . . . 54
4.10 RFIDloopontheHFlayer . . . . . . . . . . . . . . . . . . . . . . . . 54
4.11 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Chapter 5. DVD or CD Tag 57
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
5.2 Thedisctagantenna . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
5.3 Testingthetag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
5.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Chapter 6. Integrated Antenna Matching Network 67
6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
6.2 AsmallUHFloop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
6.3 Testingtheintegratedmatchingnetwork . . . . . . . . . . . . . . . 72
6.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Contents v
Chapter 7. Increasing the UHF Field Near Metal 74
7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
7.2 Electromagneticabsorbermaterial . . . . . . . . . . . . . . . . . . . 75
7.3 Designingatagforametalsurface . . . . . . . . . . . . . . . . . . . 77
7.4 Fabricatingatagforametalsurface . . . . . . . . . . . . . . . . . . 78
7.5 Measurementsontheabsorbermaterial . . . . . . . . . . . . . . . . 82
7.6 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Chapter 8. A Drill String Identi(cid:12)cation Tag 85
8.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
8.2 Constructionofthetestwell . . . . . . . . . . . . . . . . . . . . . . . 86
8.3 Constructionofadrillstringmodel . . . . . . . . . . . . . . . . . . . 88
8.4 Constructionoftestcoils . . . . . . . . . . . . . . . . . . . . . . . . . 89
8.4.1 Impedanceinsidethewell . . . . . . . . . . . . . . . . . . . . 89
8.4.2 Calculationofsourcevoltagefromcoils . . . . . . . . . . . . 89
8.4.3 Powerfromcoilinamagneticfield . . . . . . . . . . . . . . . 92
8.5 Availablesourcepower . . . . . . . . . . . . . . . . . . . . . . . . . . 92
8.6 On-sitenoisemeasurements . . . . . . . . . . . . . . . . . . . . . . . 95
8.6.1 Equipmentused . . . . . . . . . . . . . . . . . . . . . . . . . 95
8.6.2 Platformmeasurements . . . . . . . . . . . . . . . . . . . . . 96
8.7 Availablesourcepowerinoctagonantennafield . . . . . . . . . . . 98
8.8 Reduceddepthofthewell . . . . . . . . . . . . . . . . . . . . . . . . 100
8.9 Empiricalresults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
8.9.1 Amountofdetuning . . . . . . . . . . . . . . . . . . . . . . . 103
8.9.2 Changeofavailablesourcepower . . . . . . . . . . . . . . . 104
8.10 Designofatag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
8.11 Constructionofatag . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
8.12 Numericalanalysisofataginametalwell . . . . . . . . . . . . . . 109
8.13 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Chapter 9. Current Reference 114
9.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
9.2 MOSFEToperationinweakinversion . . . . . . . . . . . . . . . . . 115
9.3 Circuitstability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
9.4 Start-upcircuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
9.5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Contents vi
Chapter 10.Random-Number Oscillator 122
10.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
10.2 Designinganunstableoscillator . . . . . . . . . . . . . . . . . . . . . 125
10.3 Clockextractionfromthecarrier . . . . . . . . . . . . . . . . . . . . 127
10.4 Anunstableoscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
10.5 Animprovedunstableoscillator . . . . . . . . . . . . . . . . . . . . 135
10.5.1 Long-termasynchronousoscillatorstability . . . . . . . . . . 135
10.6 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Chapter 11.HF Recti(cid:12)ers 140
11.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
11.2 Pointstoconsiderforrectifierdesign . . . . . . . . . . . . . . . . . . 141
11.3 TheP-switchN-dioderectifier . . . . . . . . . . . . . . . . . . . . . . 142
11.3.1 Thebasicrectifierconfiguration . . . . . . . . . . . . . . . . 142
11.3.2 TheCMOSrealisation . . . . . . . . . . . . . . . . . . . . . . 143
11.3.3 Circuitoperation . . . . . . . . . . . . . . . . . . . . . . . . . 145
11.3.4 ReducingthegainoftheparasiticverticalPNP . . . . . . . . 146
11.3.5 Explanationofguardrings . . . . . . . . . . . . . . . . . . . 147
11.3.6 Placementoftheelements . . . . . . . . . . . . . . . . . . . . 147
11.4 TheN-diodeN-dioderectifier . . . . . . . . . . . . . . . . . . . . . . 149
11.4.1 Layoutconsiderations . . . . . . . . . . . . . . . . . . . . . . 152
11.5 Electrostaticdischargeprotection . . . . . . . . . . . . . . . . . . . . 153
11.5.1 Protectingtheantennaterminals . . . . . . . . . . . . . . . . 153
11.6 TheN-diodeN-switchrectifier . . . . . . . . . . . . . . . . . . . . . 156
11.7 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Chapter 12.Passive Shunt Regulators 158
12.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
12.2 Modulationdetectors . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
12.2.1 TheAMdetector . . . . . . . . . . . . . . . . . . . . . . . . . 159
12.2.2 Thevoltagecomparator . . . . . . . . . . . . . . . . . . . . . 160
12.2.3 Choosingthenominalcurrent . . . . . . . . . . . . . . . . . 160
12.2.4 Alow-passfilter . . . . . . . . . . . . . . . . . . . . . . . . . 161
Contents vii
12.2.5 Avoltage-pulse-detectcircuit . . . . . . . . . . . . . . . . . . 162
12.3 Theregulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
12.4 Regulatordesign . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
12.4.1 Maximum-stressmeasurements . . . . . . . . . . . . . . . . 167
12.4.2 Thebasicshuntregulator . . . . . . . . . . . . . . . . . . . . 168
12.4.3 Alaggingregulatorwithacapacitor . . . . . . . . . . . . . . 171
12.4.4 Step-inputstability . . . . . . . . . . . . . . . . . . . . . . . . 172
12.4.5 Alaggingregulatorwithoutacapacitor . . . . . . . . . . . . 173
12.5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
Chapter 13.A Zero-Power On-Wafer Detector 176
13.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
13.2 Circuitoperation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178
13.3 Specificimplementation . . . . . . . . . . . . . . . . . . . . . . . . . 179
13.4 Verificationofthecircuit . . . . . . . . . . . . . . . . . . . . . . . . . 180
13.5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183
Chapter 14.Conclusion 184
14.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
14.2 Antennas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
14.3 Waves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188
14.4 Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189
14.5 Validation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192
14.6 Possiblefurtherwork . . . . . . . . . . . . . . . . . . . . . . . . . . . 192
Bibliography 193
Abstract
High-performance electronic labelling systems require the separate components
to be designed in an optimum way and with a consideration of their interactions
with other components in the system. As with many system designs many as-
pects of the electrical and electronic discipline must be pursued with skill for a
successfuldesigntoemerge. Inadditiontodealingwiththesematters,theauthor
considers low cost and long range along with manufacturability as key criteria
for a high-performance labelling system and thus has kept these aspects in mind
throughoutthecomponentdesignprocess.
Thefirstpartoftheworkdescribesthedesignofbothnear-fieldandfar-fieldUHF
antennas including a UHF antenna which is combined with an HF antenna. In a
second part of the work are investigations of techniques for reading UHF tags on
a metal surface and HF tags inside a hole formed in metal. Finally, the designs
oflow-powerandlow-costmicroelectroniccircuitsforpassivetagsarediscussed.
Each system element designed by the author has been fabricated for successful
empiricalevaluation.
viii
Statement of Originality
Name: Program:
This work contains no material which has been accepted for the award of any
other degree or diploma in any university or other tertiary institution to
David M. Hall and, to the best of my knowledge and belief, contains no material
previously published or written by another person, except where due reference
hasbeenmadeinthetext.
Igiveconsenttothiscopyofmythesis,whendepositedintheUniversityLibrary,
being made available for loan and photocopying, subject to the provisions of the
CopyrightAct1968.
I also give permission for the digital version of my thesis to be made available
ontheweb,viatheUniversity’sdigitalresearchrepository,theLibrarycatalogue,
the Australasian Digital Theses Program (ADTP) and also through web search
engines, unless permission has been granted by the University to restrict access
foraperiodoftime.
Signature: Date:
ix
Acknowledgments
The author would like to thank his supervisor Professor Peter H. Cole for his
tireless support in the study for and writing of this thesis. Professor Cole has
provided the author with insights into RFID unequalled in this field of study. He
hasalsoprovidedfundsforfabricationsandsustenanceduringmanyalongnight
inthelaboratory.
The author would also like to thank the following persons in no order of impor-
tance.
GordonAllisonforhisskillsinthemachineshop.
SaidAlsarawiforhelpwithlayouttools,OpAmps,LaTex,andUNIX.
AndrewBeaumont-SmithforhelpwithlayouttoolsandSPICEextraction.
GarethFinchforluggagetagmeasurements.
BennoFleckerforbookandfashiontagmeasurements.
AlfGrassoforVLSIfabrication.
StephenGuestforgeneraluseoffacilities.
NathanHuforhelpwithLaTex.
BenJamaliforhelpwithUNIX.
KinSeongLeongforhelparoundthelaboratory.
IanLinkeforaccesstotheworkshop.
PhilippeMartinforchipassembly.
AlastairMcArthurforhelpwithpatents.
AliMoiniforhelpwithVLSItapeout.
MunLengNgforhelparoundthelaboratoryandwithLaTex.
DamithRanasingheforhelpwithMATLAB.
x