ii

ABSTRACT

Radio Frequency Identification (RFID) is a rapidly developing wireless technology

that utilizes electromagnetic waves for the automatic identification and tracking of

objects. An RFID system composes of a tag, which is attached to an object and uses

an antenna to communicate with a reader. This research work presents the design of

microwave RFID tag antenna and dual-band antenna with a modified Minkowski

fractal. A dual-band antenna with a modified Minkowski fractal was selected, due to

its many attractive characteristics. This fractal geometry has space-filling properties

that can be utilized to miniaturize antennas. In addition, the self-similarity properties

of fractals make them especially suitable to design dual-band antennas. These

proposed antennas are designed using the electromagnetic simulation software called

CST for a passive RFID tag operating in the Microwave frequency band. A single

band tag antenna was designed and simulated for 2.45GHz. A high gain (5.842dB), a

good impedance matching with the microchip (-30.0 dB Return Loss) and a

satisfactory read range performance (upto 5 m) was obtained. A Dual-band antenna

with a modified Minkowski fractal has been designed, fabricated, and measured. The

proposed antenna is fed by microstrip line, and it consists of modified Minkowski

radiating element on the top layer and partial ground on the bottom layer. Simulated

and measured performance results are presented for a modified Minkowski small size

(2.3x3.0cm) fractal antenna. The measured result for return loss of the proposed

antenna shows that the antenna has two operating frequency bandwidths namely, the

lower frequency from 2.36-2.525GHz and the upper frequency from 5.735-5.89GHz.

The measurement results showed good agreement with the simulation result. One

approach of designing RFID tag is that the tag should be less sensitive to the various

types of objects. The effects of obstacles on antenna’s characteristics have been

investigated by placing the tag antenna against a metallic, rubber, glass and wood

surfaces. Simulation results show slight variations which is within tolerance range.

iii

CST

2.45GHz5.842 dB

-30.0 dB Return Loss5

Microstrip

2.3x3.0

2.36-2.525GHz5.735-5.89 GHz

iv

APPROVAL PAGE

I certify that I have supervised and read this study and that in my opinion, it conforms

to acceptable standards of scholarly presentation and is fully adequate, in scope and

quality, as a thesis for the degree of Master of Science (Communications Engineering)

………………………………

MD Rafiqul Islam

Supervisor

I certify that I have read this study and that in my opinion it conforms to acceptable

standards of scholarly presentation and is fully adequate, in scope and quality, as a

thesis for the degree of Master of Science (Communications Engineering)

………………………………

Musse Mohamud Ahmed

Examiner

This dissertation was submitted to the Department of Electrical and Computer

Engineering and is accepted as a fulfilment of the requirements for the degree of

Master of Science (Communications Engineering)

………………………………

Othman O. Khalifa

Head, Department of Electrical

and Computer Engineering

This dissertation was submitted to the Kulliyyah of Engineering and is accepted as

fulfilment of the requirement for the degree of Master of Science (Communications

Engineering)

……………………………….

Amir Akramin Shafie

Dean, Kulliyyah of Engineering

v

DECLARATION

I hereby declare that this dissertation is the result of my own investigations, except

where otherwise stated. I also declare that it has not been previously or concurrently

submitted as a whole for any other degrees at IIUM or other institutions.

Abubeker Abdulkerim Yussuf

Signature …………………… Date ………………..

vi

INTERNATIONAL ISLAMIC UNIVERSITY MALAYSIA

DECLARATION OF COPYRIGHT AND AFFIRMATION

OF FAIR USE OF UNPUBLISHED RESEARCH

Copyright © 2011 by International Islamic University Malaysia.All rights reserved.

DESIGN OF RFID TAG ANTENNA MATCHED TO MICROCHIP

IMPEDANCE

I hereby affirm that the International Islamic University Malaysia (IIUM) hold all

rights in the copyright of this work and henceforth any reproduction or use in any

form or by means whatsoever is prohibited without the written consent of IIUM. No

part of this unpublished research may be reproduced, stored in a retrieval system, or

transmitted, in any form or by any means, electronic, mechanical, photocopying,

recording or otherwise without prior written permission of the copyright holder.

Affirmed by Abubeker Abdulkerim Yussuf

---------------------------- ----------------------

Signature Date

vii

ACKNOWLEDGEMENTS

First and foremost, I am so thankful to Allah (s.w.t) for the completion of this thesis. I

would like to express my gratitude and deep appreciation to my Assoc. Prof. Dr. MD

Rafiqul Islam for his guidance, positive suggestions, and also support and confidence

in my work. His patience and encouragement were invaluable to me throughout the

course of this research. He pushed me to perform to the best of my abilities and gave

me opportunities and exposure I never would have had if I had not been with him. For

that, I am extremely grateful.

My heartfelt thanks are to my wonderful parents, brothers and sisters who have been

an incredible pillar of support. Their constant moral support has been the foundations

of all my accomplishments. Thanks for standing by me in all good and tough times.

I would also like to thank my co-supervisors Assoc. Prof. Dr. AHM Zahirul Alam and

Assoc. Prof. Dr. Sheroz Khan for their sincere help in actualizing my research. Bro.

Mohd Shukor at the Antenna and Wave Propagations Lab and Bro. Shahlan Bin Dalil

at the Mechatronics Workshop have been very helpful during my research work. My

sincere gratitude goes to them.

Last but not least, I am very grateful to the helpful staff at the Department of

Electrical and Computer Engineering. Last but not least, Ibrahim Abdulrihman , Mimi

Aminah Wan Nordin and Abdul-Aziz Abudo have been such great friends to have

them around and spend interesting time together working on our research projects at

RF Design Lab.

viii

TABLE OF CONTENTS

Abstract ........................................................................................................................... ii

Approval Page ................................................................................................................. iii

Declaration Page ............................................................................................................. iv

Copyright Page ................................................................................................................ v

Acknowledgements ......................................................................................................... vi

Table of Contents ............................................................................................................ vii

List of Tables .................................................................................................................. x

List of Figures ................................................................................................................. xi

List of Abbreviations ...................................................................................................... xv

CHAPTER ONE: INTRODUCTION ......................................................................... 1

1.1 Overview ........................................................................................................ 1

1.2 Problem Statement and Significance ............................................................. 3

1.3 Research Objectives ....................................................................................... 3

1.4 Research Methodology .................................................................................. 4

1.5 Research Scope .............................................................................................. 7

1.6 Thesis Outline ................................................................................................ 7

CHAPTER TWO: RFID TAG ANTENNA ................................................................ 8

2.1 Introduction .................................................................................................... 8

2.2 RFID Tag Antenna ........................................................................................ 10

2.3 RFID Tag Antenna Types .............................................................................. 12

2.3.1 Passive RFID Tag Antenna ................................................................. 12

2.3.2 Semi-Passive RFID Tag Antenna ....................................................... 12

2.3.3 Active RFID Tag Antenna .................................................................. 13

2.4 Operating Frequency Ranges ......................................................................... 14

2.4.1 Low-Frequency (LF) ........................................................................... 14

2.4.2 High-Frequency (HF) .......................................................................... 15

2.4.3 Ultrahigh-Frequency (UHF) ............................................................... 15

2.4.4 Microwave-Frequency ........................................................................ 16

2.5 Principle of Operating Passive RFID Tag ..................................................... 18

2.5.1 Inductive Coupling .............................................................................. 18

2.5.2 Electromagnetic backscatter ............................................................... 19

2.6 Antenna Theory ............................................................................................ 21

2.6.1 Gain ..................................................................................................... 21

2.6.2 Resonant frequency and bandwidth .................................................... 21

2.6.3 Directivity ........................................................................................... 22

2.6.4 Polarization ......................................................................................... 22

2.6.5 Radiation pattern ................................................................................. 23

2.6.6 Input impedance and Reflection Coefficient ...................................... 23

2.6.7 Smith Chart Analysis .......................................................................... 24

2.6.8 Power Transmission Coefficient ......................................................... 26

ix

2.7 Power Link Budget ........................................................................................ 27

2.8 Backscatter Communication Link ................................................................. 28

2.9 The Electromagnetic Waves near Metallic Surfaces ..................................... 29

2.9.1 The Effects of Metallic Surfaces on RFID Tag Antennas .................. 32

2.9.2 Research of RFID tag existing on Metallic Objects ........................... 35

2.10 Fractal Geometry ........................................................................................ 38

2.11 Major Known Features of Fractal ............................................................... 40

2.12 Summary ..................................................................................................... 41

CHAPTER THREE: DESIGN OF MICRWAVE BAND RFID TAG

ANTENNA ..................................................................................................................... 42

3.1 Introduction .................................................................................................... 42

3.2 A Patch Antenna for Microwave RFID Tag Design ..................................... 43

3.3 Microchip Impedance Matched Antenna ....................................................... 45

3.4 Theoretical Calculations ................................................................................ 48

3.5 Simulations .................................................................................................... 51

3.5.1 Simulation of 50Ω-Matched Antenna ................................................. 51

3.5.2 Simulation of Antenna Impedance Transformed into Conjugate

Microchip Impedance ........................................................................... 55

3.6 Summary ....................................................................................................... 61

CHAPTER FOUR: MICROWAVE RFID TAG ANTENNA

MOUNTABLE ON AND MOUNTING PLATFORMS ............ 62

4.1 Introduction .................................................................................................... 62

4.2 Microwave RFID Tag Antenna Mounted on Metallic

Object ............................................................................................................. 64

4.3 Microwave RFID Tag Antenna Mounted on Glass

Material .......................................................................................................... 69

4.4 Microwave RFID Tag Antenna Mounted on Wood

Material .......................................................................................................... 74

4.5 Microwave RFID Tag Antenna Mounted on Rubber

Material .......................................................................................................... 78

4.6 Microwave Band RFID Tag Antenna Mounted on

Various Types of Dielectric Platforms .......................................................... 82

4.7 Summary ........................................................................................................ 89

CHAPTER FIVE: DESIGN OF A MODIFIED MINKOWSKI FRACTUAL

MICROSTRIP ANTENN FOR RFID DUAL-BAND

APPLICAION ................................................................................ 90 5.1 Introduction .................................................................................................... 90

5.2 Fractal Antenna Simulations.......................................................................... 94

5.3 Antenna Fabrication and Measurements ....................................................... 103

5.3.1 Layout of the Microstrip Antenna ...................................................... 103

5.3.2 Cutting up-to-scale .............................................................................. 104

5.3.3 Lamination, Scanning and film creation ............................................. 105

5.3.4 Removing the copper .......................................................................... 106

x

5.3.5 Connector Fixing................................................................................. 107

5.3.6 The return loss ..................................................................................... 109

5.4 Summary ........................................................................................................ 110

CHAPTER SIX: CONCLUSION AND RECOMMENDATION ............................. 111

6.1 Conclusion ..................................................................................................... 111

6.2 Recommendation. ......................................................................................... 113

BIBLIOGRAPHY ......................................................................................................... 114

APPENDIX A: Copolarization and Crosspolarization ................................................... 118

APPENDIX B: Patch dimension Calculation Using Matlab .......................................... 119

APPENDIX C: Design of A Modified Minkowski ........................................................ 120

xi

LIST OF TABLES

Table No. Page No.

2.1 Decades of RFID 9

2.2 Summary of key RFID frequencies and applications 17

3.1 Geometrical and Dielectric parameters of the

microstrip patch Antenna Structure 44

3.2 Electrical characteristics of microchip 47

3.3 RFID tag key parameters 60

3.4 Comparison of single band RFID tag antennas 61

4.1 Effect of various objects on the tag at 2.45 GHz 83

5.1 Geometrical and Dielectric parameters of the Antenna Structure 95

5.2 Simulated results of Gain, Radiation Efficiency and Return Loss

of antenna at frequency 2.45GHz and 5.8GHz 100

5.3 Comparison of dual band RFID tag antennas 100

xii

LIST OF FIGURES

Figure No. Page No.

1.1 Flow Chart of the RFID tag antenna design process 6

2.1 Components of a Passive RFID System 9

2.2 Operating frequency Range 14

2.3 Various RFID applications 17

2.4 Operation principle of an inductively coupled transponder 18

2.5 Operating principle of a backscatter transponder 20

2.6 Equivalent circuit of Power transfer in the RFID tag 24

2.7 Desired positions of inductive antenna and capacitive chip

reflection factors in the Smith Chart 25

2.8 Electromagnetic Boundary conditions. (a) between two media; and

(b) at the interface of PEC. 29

2.9 Equivalent models for electric and Magnetic source of radiation

fields near a metallic surface 30

2.10 Boundary conditions. (a) Electric fields; and (b) magnetic

fields near a metallic surface 31

2.11 Patch antenna with EBG ground plane and two-layer substrate 36

2.12 RFID Tag Using a Planar Inverted-F Antenna 36

2.13 Shorted Microstrip Patch Antennas Using Inductively

Coupled Feed for RFID 37

2.14 Generation of Three Iterations of Fractal Curves 40

3.1 Structure of the RFID tag antenna 45

3.2 Smith chart visualization of the matching impedance 46

3.3 Simulation model of the tag antenna without

an inset and a microstrip line 52

xiii

3.4 Simulated return loss before the patch length adjustment 52

3.5 Simulated return loss at 2.45GHz after the patch length adjustment 53

3.6 Simulated return loss at 2.45GHz after the patch length adjustment

an inset and a microstrip line 54

3.7 Smith chart visualization of the impedance of

the conventional patch antenna 54

3.8 Proposed structure of the RFID tag antenna 56

3.9 Smith chart visualization of the impedance of the patch

antenna using inset microstrip line feed 56

3.10 Simulated impedance plots of the patch antenna 57

3.11 Simulated Gain pattern of the tag antenna 57

3.12 Simulated directivity pattern of the tag antenna 58

3.13 Simulated far-field radiation patterns at 2.45 GHz

for proposed antenna 59

3.14 Simulated return loss and transmission coefficient 59

4.1 Structure of the microstrip patches for Microwve tag antennas 64

4.2 Simulated impedance characteristics with different sizes

of metallic platforms 65

4.3 Simulated gain for different sizes of metallic platforms 66

4.4 Simulated Return loss for different sizes of metallic platforms 67

4.5 Simulated radiation patterns with different sizes of metal platforms 69

4.6 Simulated impedance characteristics with different

sizes of glass platforms 70

4.7 Simulated gain for different sizes of glass platforms 71

4.8 Simulated Return loss for different sizes of glass platforms 71

4.9 Simulated radiation patterns with different sizes of glass platforms 73


sizes of wood platforms 75

xiv

4.11 Simulated radiation efficiency for different sizes of wood platforms 75

4.12 Simulated Return loss for different sizes of wood platforms 76

4.13 Simulated radiation patterns with different sizes of wood platforms 77


sizes of rubber platforms 79

4.15 Simulated gain for different sizes of rubber platforms 79

4.16 Simulated Return loss for different sizes of rubber platforms 80

4.17 Simulated radiation patterns with different sizes of rubber platforms 81

4.18 Simulated impedance characteristics with 1.0λ x 1.0λ of

various platforms 84

4.18 Simulated impedance characteristics with 1.5λ x 1.5λ of


4.20 Simulated gain for different sizes of various platforms 86

4.21 Simulated Return loss for different sizes of various platforms 86

4.22 Simulated radiation patterns with different sizes of


5.1 Generation procedure for the Minkowski fractal curve 91

5.2 Geometry of dual-band antennas with a modified

Minkowski fractal curve 94

5.3 Dual-band antennas with a second stage

Minkowski fractal curve layout 96

5.4 Return loss of dual-band antennas with a second stage


5.5 Parameterization of the second stage

Minkowski fractal curve S11 97

5.6 Return loss of dual-band antennas with a modified


5.7 Simulated Gain and Efficiency of antenna

at lower operating frequency 98

xv

5.8 Simulated Gain and Efficiency of antenna

at upper operating frequency 98

5.9 Simulated far-field radiation patterns

at 2.45 GHz for proposed antenna 99

5.10 Simulated far-field radiation patterns

at 5.8 GHz for proposed antenna 99

5.11 Read range of the antenna

at lower operating frequency 102

5.12 Read range of the antenna

at upper operating frequency 102

5.13 up-to the scale image: (a) Front side (Patch); (b) Rear side 103

5.14 CNC drilling machine 104

5.15 Laminating machine 105

5.16 Ultraviolet Machine 106

5.17 Bench Module machine 107

5.18 SMA edge mount connector 108

5.19 Fabricated Multi-band antennas with a modified

Minkowski fractal Curve layout 108

5.20 Return loss Comparison 109

xvi

LIST OF ABBREVIATIONS

RFID Radio frequency identification

FIT Finite Integration Technique

CST Computer Simulation Technology

3D 3-dimension

EM Electromagnetic

IFF Identify-friend-or-foe

EAS Electronic article surveillance

LF Low Frequency

HF High Frequency

UHF Ultrahigh Frequency

PIFA Planar inverted-F antenna

TMM Thermoset microwave materials

FR4 Flame Retardant 4 (printed circuit boards)

1

CHAPTER ONE

INTROUCTION

1.1 OVERVIEW

Radio frequency identification (RFID), which was developed around World War II,

provides wireless identification and tracking capability for various applications

(Finkenzeller, 2003). The purpose of an RFID system is to enable data to be stored

and transmitted by a mobile tag, called an RFID tag, which is then read by an RFID

reader and subsequently processed the data according to the needs of a particular

application. The data transmitted by the tag may be used to provide identification

location information, or as a product tag. RFID tag is an object that can be attached to

a product, animal, and human being for the purpose of identification and tracking. In

term of architecture, RFID tags contain an integrated circuit for storing and processing

information, modulating and demodulating a radio frequency signal, specify or get rid

of this, and an antenna for receiving and transmitting the signal. There are three

classes of RFID tag, dependent on power requirement, as follows: 1. Passive tags are

very low in cost but tend to be limited in terms of range and data rate. They can only

respond once powered by the reader, which may take some time. 2. Semi-active tags

have a limited power supply, which allows faster operation. 3. Active tags have

enough on-board battery power to allow ‘broadcast’ of their presence to readers and

high data rate communications. In a typical passive RFID system, each individual

object is equipped with a small and inexpensive tag which comprises an antenna and

an application-specific integrated circuit (microchip) that is given a unique electronic

product code (Daniel Hunt et al ,2007). The reader emits a signal to activate the tag,

2

which passes through the electromagnetic field zone generated by a reader antenna

and decodes the data encoded in the tag’s microchip. The data are then passed to a

host computer for processing. The signal coming from the reader must have enough

power to activate the tag microchip, perform data processing, and transmit back a

modulated string over the required reading distance. Since the maximum output power

of the reader is constrained to local regulated effective isotropically radiated power

(EIRP) (Ilyas, 2008), the reading distance achieved is dependent on the performance

of the tag, that is, the microchip selected and the characteristics of the antenna.

Furthermore, tag antenna design issues will be addressed. Since the frequency

available for RFID applications varies from very low (below 135 kHz) to microwave

(up to 24.5 GHz), antenna designs will vary with specific applications. The important

considerations are to achieve the required radiation characteristics and impedance

matching between the antenna and the microchip (Loo et al, 2008). The microchip

receives power from the antenna and responds by varying its input impedance and

thus modulating the backscattered signal with data. In order to achieve maximum

operating condition, the antenna impedance should be matched correctly to the chip

impedance. When both chip impedance and antenna impedance are complex,

calculating an accurate power reflection coefficient for tag antenna design is a

challenging process. Important RFID tag characteristics are maximum range and

orientation sensitivity. The effect of the environment on RFID tags, because the tag is

often attached to a specific object in practical applications. The performance of the

RFID tag is strongly dependent on the properties of the attached object. (Lehpamer,

2008)

3

1.2 PROBLEM STATEMENT AND SIGNIFICANCE

Metallic objects effect considerably degrade the performance of the far-field tag

antennas, lower its radiation efficiency, cause a reduction in the reading distance and

distort the impedance when the antenna is placed close to objects. This in general

causes fluctuation of the complex impedance of the RFID antenna and that of the chip,

which in turn leads to mismatching between the two elements. The complex

impedance of the IC requires a conjugate complex impedance match at the antenna

end. This is a real challenge since the chip impedance varies at different power levels

and frequencies. In order to maximize the tag reading range, impedance has to be

matched at various IC power levels such as at minimum threshold power. Microwave

band RFID tag antenna use of a microstrip patch antenna has been proposed to

minimize the above mentioned issues.

1.3 RESEARCH OBJECTIVES

The main objectives of this research work are:

i. To design single band RFID tag antenna.

ii. To evaluate the performance of designed tag antenna in different vicinity

and mounting platform environment.

iii. To evaluate the antenna for proper impedance matching.

iv. To design and fabricate dual-band tag antenna, characterize and compare

with simulation results.

4

1.4 RESEARCH METHODOLOGY

The research work on tag antenna designs covers the theoretical tag antenna design,

tag antenna simulation, tag antenna prototyping and measurement. The steps those

have been taken towards achieving the project’s objective are as follows. The steps are

then summarized in the flow chart, as shown in Figure 1.1:

a) Literature Review and define the requirement of the tag

A literature review has been made in order to see similar works that has been done. A

review of previous techniques that has been applied for the enhancement of the gain

and improving the radiation efficiency of antennas has been studied. The compatibility

of the techniques to be used in this research work has also been investigated. The

application was decided, and the tag requirement has also been studied. Parameters

such as the type of the tag (passive), operation frequency (microwave frequency), size

and cost have all been determined by the application.

b) Determine the Materials for the Antenna Construction

The effect of different substrate used for the construction of the RFID antennas has

been studied, in order to determine the most suitable material to be used.

c) Determine the RF Impedance

The complex impedance of the RFID chip has then be determined. This has enabled a

matching to be designed to properly match the impedance of the designed antenna.

5

d) Design the Antenna and Its Parameters

The antenna has been designed to suit the requirement of the application, based on

several parameters such as the impedance, gain and radiation efficiency. Techniques

upon how to improve the gain, reading range and the radiation efficiency have been

implemented in order for the objective of the project to be met, a patch antenna and a

modified Minkowski fractal for the RFID antenna structures. The design has then

been simulated, and different parameters have been optimized to suit the

requirements.

e) Simulate and perform parametric study

The antenna is simulated using CST electromagnetic simulator and simulations tools

that utilize the Finite Integration Technique (FIT). The antenna is first modeled and

simulated. Then parametric study and optimization is performed by monitoring the

antenna radiation pattern, input impedance and directivity until the desired design

requirements are met in simulation. The simulation software that was used for the

antenna design in this thesis was 3D EM Field Simulation Computer Simulation

Technology (CST).

f) Final Design

If the design requirements are satisfied, the antenna design is ready. Otherwise, the

design is further modified and optimized until requirements are met.

6

Figure1.1: Flow Chart of the RFID tag antenna design process

Literature

Review

Determine the Materials for antenna construction

Determine RF impedance of packaged ASIC

Simulate (CST Microwave Studio)

Perform parametric study and optimization

Build the antenna structure

Define the requirement of the tag

Modify the antenna

dimensions

Criteria

Met?

End

7

1.5 RESEARCH SCOPE

The main theme of this research work is to investigate RFID tag antenna design

procedures and problems; antenna used for metallic object and complex conjugate

matching and size reduction techniques for operational bandwidth, gain, radiation

pattern and radiation efficiency for Microwave RFID tags. For each design solution,

the roles of the main geometrical and factual parameters over the impedance tuning

are investigated.

1.6 THESIS OUTLINE

This thesis is organized into 6 chapters.

Chapter one provides a brief introduction to Radio Frequency Identification (RFID). It

also discusses the objectives of the research work done and research methodology.

Chapter two deals with background of RFID and related work. And also the history of

RFID and the brief introduction to RFID systems are presented.

In chapter three, firstly the design of a Microwave RFID tag suitable for operation on

metallic surfaces and consisting of a full size microstrip patch antenna is presented.

Discussion of the design considerations and concepts is included. The results of

theoretical calculations and simulations are shown.

In chapter four, Microwave tag antennas which are mountable on different object are

introduced and analyzed.

Chapter five presents a dual-band fractal shape tag antenna design for RFID

applications. In this chapter, design concepts and steps taken to achieve the final tag

prototypes are described. Simulation and measurement results are shown.

Chapter six concludes this thesis with a summary of the work done and suggestion for

future work of research.

8

CHAPTER TWO

RFID TAG ANTENNA

2.1. INTRODUCTION

The origin of RFID technology can be traced back to World War II. The Germans,

Japanese, Americans and British were all using radar to warn of approaching planes

while they were still miles away; however, it was impossible to distinguish enemy

planes from allied ones. The British developed the first active identify-friend-or-foe

(IFF) system. By just putting a transmitter on each British plane, it received signals

from the aircrafts. This identified the planes as friendly ( Landt, 2005).

The advances in radar and RF communications systems continued after World

War II through the 1950s and 1960s, as described in Table 2.1. In the 1960s,

application field trials were initiated, followed by first commercial product.

Companies were investigating solutions for anti-theft, which revolutionized the whole

RFID industry. They investigated anti-theft systems that utilized RF waves to monitor

if an item was paid or not. This was the start of the 1-bit electronic article surveillance

(EAS) tags by Sensormatic, Checkpoint. This is by far the most commonly used RFID

application.In the 1970s, various governments developed identification technology to

track military equipment and personnel (Dobkin, 2008). By the late 1970s this

identification technology was used for identification and temperature sensing of cattle.

However, the wide use of the technology was possible only by late 1980s and 1990s

when the semiconductor companies were able to achieve improved performance with

size and cost reduction. This enabled RFID systems to be used in many new practical

applications. Recently, RFID has experienced a tremendous growth, due to

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