NG NfENC I TANN UNIVERSITI MALAYSIA SARAWAK 2002

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SIMULATION 011 A 10 GIIZ RECTANGULAR MICROSrIRIP PATCH ANTENNA

USING MICROWAVE OFFICE 2000

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UNIVERSITI MALAYSIA SARAWAK

2002

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SIMULATION OF A 10 GHZ RECTANGULAR MICROSTRIP PATCH ANTENNA USING MICROWAVE OFFICE 2000

NG MENG HANN

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Borang Penyerahan Tesis Universiti Malaysia Sarawak

R13a BORANG PENYERAHAN THESIS

Judul: Simulation of a 10 GHz Rectangular Microstrip Patch Antenna

Using MicroWave Office 2000

SESI PENGAJIAN: 2001/2002

Saya NG MENG HANN

(HURUF BESAR)

mengaku membenarkan tesis ini disimpan di Pusat Khidmat Maklumat Akademik, Universiti Malaysia Sarawak dengan syarat-syarat kegunaan seperti berikut:

1. Hakmilik kertas projek adalah di bawah nama penulis melainkan penulisan sebagai projek bersama dan dibiayai oleh UNIMAS, hakmiliknya adalah kepunyaan UNIMAS.

2. Naskhah salinan di dalam bentuk kertas atau mikro hanya boleh dibuat dengan kebenaran bertulis daripada penulis.

3. Pusat Khidmat Maklumat Akademik, UNIMAS dibenarkan membuat salinan untuk pengajian mereka.

4. Kertas projek hanya boleh diterbitkan dengan kebenaran penulis. Bayaran royalti adalah mengikut kadar yang dipersetujui kelak.

5. * Saya membenarkan/tidak membenarkan Perpustakaan membuat salinan kertas projek ini sebagai bahan pertukaran di antara institusi pengajian tinggi.

6. ** Sila tandakan () ýý

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SULIT

TERHAD

TIDAK TERHAD

(Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia seperti yang termaktub di dalam AKTA RAHSIA RASMI 1972)

(Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasi/

badan di mana penyelidikan dijalankan)

(TANDATANGAN PENULIS) Alamat Tetap: NO. 401. BLOK A3.

SEKSYEN 2, WANGSA MAJU. 53300 KUALA LUMPUR.

EN. KISMET HONG PING Nama Penyelia

Tarikh: 25 MARCH 2002 Tarikh: 25 MARCH 2002

CATATAN *

**

Potong yang tidak berkenaan

Jika kertas Projek ini SULIT atau TERHAD, sila lampirkan surat daripada pihak berkuasa/

organisasi berkenaan dengan menyertakan sekali tempoh kertas projek. Ini perlu dikelaskan sebagai SULIT atau TERHAD.

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SUPERVISOR'S CERTIFICATION

After having read this thesis paper prepared by NG MENG HANN entitled SIMULATION OF A 10 GHZ RECTANGULAR MICROSTRIP PATCH ANTENNA USING MICROWAVE OFFICE 2000, this supervisory camp is satisfied with the thesis papers a fulfillment for the award of a bachelor's degree with Honours in Electronic and Telecommunication Engineering

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SIMULATION OF A 10 GHZ RECTANGULAR MICROSTRIP PATCH ANTENNA USING MICROWAVE OFFICE 2000

NG MENG HANN

Tesis Dikemukakan Kepada

Fakulti Kejuruteraan, Universiti Malaysia Sarawak Sebagai Memenuhi Sebahagian daripada Syarat

Penganugerahan Sarjana Muda Kejuruteraan

Dengan Kepujian (Kejuruteraan Elektronik dan Telekomunikasi)

2002

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Dedicated to my beloved family and loved ones

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ACKNOWLEDGEMENTS

The researcher would like to express his sincere gratitude and appreciation to his Project Supervisor, Mr. Kismet Hong Ping for his inspiring guidance and encouragement throughout the duration of the project.

In addition, the researcher would like to specifically thank his family and loved ones for giving their support, help and encouragement during the drift and difficult encounters while doing the research and report writing. The researcher would also like to thank Mr. Thelaha Masri for his many thoughtful tips throughout the duration of the project and early guidance in understanding the art of antenna design. Last but not least, not forgetting everyone who had involved in one way or another to make this project a success, I would like to thank them very much for their help and support.

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ABSTRACT

This research describes the design and simulation of the rectangular microstrip patch antenna using MicroWave Office 2000 version 3.22 and subsequently derives several relationships for the purpose to determine the performance of the antenna designed.

This research involves software simulation, where several parameters comprising the frequency of operation, dielectric constant, type of dielectric material to be used, tangent loss, etc. were preset prior to the design of the antenna. MicroWave Office 2000 simulation software was used to generate the Smith Chart, VSWR, S11 Magnitude or Return Loss and Impedance Chart. From the charts generated, various results were then tabulated in tabular form. Previous works done by other researchers were also referred to.

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ABSTRAK

Kajian ini membincangkan kaedah rekaan dan simulasi "rectangular microstrip patch" antenna dengan menggunakan perisian MicroWave Office 2000 versi 3.22 dan seterusnya mentakrifkan beberapa perhubungan dengan tujuan untuk menentukan tahap pencapaian antenna yang direka. Kajian ini melibatkan penggunaan perisian simulasi, di mana beberapa parameter melibatkan frekuensi operasi, pemalar dielektrik, bahan dielektrik yang akan digunakan dan sebagainya telah ditetapkan sebelum proses simulasi dan rekaan dimulakan. Perisian ini juga digunakan untuk menghasilkan Carta Smith, VSWR, S11 Magnitude atau Carta Return Loss. Daripada keputusan kajian dalam bentuk carta, ianya kemudian ditukar ke dalam bentuk jadual. Hasil kerja yang dilakukan ahli kaji selidik juga telah digunakan sebagai rujukan.

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pIYsat. JýIaidhrat Iißaluumat AlCademi-k liNIVEKSIjI MALAYSIA SARAWAK

94304 Ku? a Samarahan

LIST OF FIGURES

ONE

TWO

INTRODUCTION 1.1 Background

1.2 Basic Types of Antennas 1.3 Objectives

LITERATURE REVIEW 2.1 Microstrip Transmission Line

2.2 Characteristics Impedance of Microstrip Lines 2.3 Dielectric Substrate

2.3.1 Dielectric Constant, e

2.4 Field Pattern of Microstrip Transmission Line

PAGE.

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2

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4 4 4 5

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2.5 Definition of Important Antenna Parameters 8

2.5.1 Radiation Pattern 8

2.5.2 Near Field, Far-field and the Rayleigh

Distance 9

2.5.3 Gain 10

2.5.4 Directivity 10

2.5.5 Efficiency 10

2.5.6 Impedance 11

2.5.7 Voltage Standing Wave Ratio (VSWR) 11

2.5.8 Bandwidth 11

THREE

2.5.9 Polarization 2.5.10 Size/Complexity 2.6 Impedance Matching 2.7 Antenna Types

2.7.1 Horn Antennas 2.7.2 Loop Antennas 2.7.3 Helical Antennas 2.7.4 Patch Antennas 2.8 Microstrip Patch Antenna

2.8.1 10 GHz Rectangular Microstrip Patch Antenna with Via Port (Coax Feed)

METHODOLOGY 3.1 Introduction 3.2 Procedures

12 12

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14 14 14

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FOUR

4.1 4.2

4.3

4.4 4.5

3.2.1 Dimensions of Interest for the Antenna 3.2.2 Patch Size Calculation

3.2.3 Cell Size Calculation

3.2.4 Filling in Substrate Information 3.2.4.1 Enclosure

3.2.4.2 Dielectric Layers 3.2.4.3 Boundaries 3.2.5 Drawing the Patch 3.2.6 Simulation and Analysis

RESULTS AND ANALYSIS Simulation Considerations Implementation

Results Analysis

Enhancement Experimentation

4.5.1 Method 1: Fixing the Dielectric Constant, E, While Varying the Dielectric Thickness 4.5.1.1 Experiment 1

4.5.1.1.1 Results 4.5.1.2 Experiment 2

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21 22 23 24 24 25 26 27

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30 31 32 33

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4.5.1.4.1 Results 37

4.5.1.5 Experiment 5 38

4.5.1.5.1 Results 38

4.5.2 Analysis of Method 1 39

4.5.3 Method 2: Varying the Dielectric Constant,

Er, While Fixing the Dielectric Thickness 40

4.5.3.1.1 Results 40

4.5.3.2.1 Results 41

4.5.3.3.1 Results 42

4.5.3.4.1 Results 43

4.5.5 Method 3: Removing Some Parts of the

Edges of the Patch 44

4.5.5.1.1 Results 45

4.5.5.2.1 Results 46

4.5.5.3.1 Results 48

4.5.5.4.1 Results 49

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FIVE

4.6 Selection Criteria for the Optimum Antenna Design 50

CONCLUSION 5.1 Conclusion

5.1.1 Comparisons with Other Researchers' Designs

5.2 Recommendations

REFERENCES BIBLIOGRAPHY APPENDIX

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56 57

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LIST OF TABLES

Tables Pages

4.1 Summaries of Results 31

4.2 Summaries of Results for Experiments 1-5 (Method 1) 39 4.3 Summaries of Results for Experiments 1-5 (Method 2) 44 4.4 Summaries of Results for Experiments 1-4 (Method 3) 50

5.1 Optimum Parameters of the Antenna 53

5.2 Various Comparisons Between the Author's Results and Other

Researchers' Results 56

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LIST OF FIGURES

Figures Page

2.1 A Microstrip Transmission Line 4

2.2 Pattern of the Electromagnetic Field of a Microstrip Line 7

2.3 Horn Antenna 14

2.4 Loop Antenna 15

2.5 Helical Antenna 16

2.6 Patch Antennas 16

3.1 Flow Chart of Methodology 20

3.2 MathCAD Work Sheet for Patch Size Calculation 22

3.3 Orientation of the Patch 23

3.4 Cell Calculator Work Sheet 24

3.5 Substrate Information Window 25

3.6 Dielectric Layers Window 26

3.7 Boundaries Window 27

3.8 Ruler Option to Measure the Patch 28

4.1 Dimension of the Patch Antenna and the Position of the Port 30

4.2 VSWR Graph 31

4.3 Magnitude Graph 31

4.4 Impedance Graph 32

4.5 Magnitude Graph (Method 1: Experiment 1) 34

4.6 Impedance Graph (Method 1: Experiment 1) 34

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4.7 VSWR Graph (Method 1: Experiment 1) 4.8 Magnitude Graph (Method 1: Experiment 2) 4.9 Impedance Graph (Method 1: Experiment 2) 4.10 VSWR Chart (Method 1: Experiment 2) 4.11 Magnitude Graph (Method 1: Experiment 3) 4.12 Impedance Graph (Method 1: Experiment 3) 4.13 VSWR Graph (Method 1: Experiment 3) 4.14 Magnitude Graph (Method 1: Experiment 4) 4.15 Impedance Graph (Method 1: Experiment 4) 4.16 VSWR Graph (Method 1: Experiment 4) 4.17 Magnitude Graph (Method 1: Experiment 5) 4.18 Impedance Graph (Method 1: Experiment 5) 4.19 VSWR Graph (Method 1: Experiment 5) 4.20 Magnitude Graph (Method 2: Experiment 1) 4.21 Impedance Graph (Method 2: Experiment 1) 4.22 VSWR Graph (Method 2: Experiment 1) 4.23 Magnitude Graph (Method 2: Experiment 2) 4.24 Impedance Graph (Method 2: Experiment 2) 4.25 VSWR Graph (Method 2: Experiment 2) 4.26 Magnitude Graph (Method 2: Experiment 3) 4.27 Impedance Graph (Method 2: Experiment 3) 4.28 VSWR Graph (Method 2: Experiment 3) 4.29 Magnitude Graph (Method 2: Experiment 4) 4.30 Impedance Graph (Method 2: Experiment 4) 4.31 VSWR Graph (Method 2: Experiment 4)

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4.32 Removal of a Portion of the Right Patch (Experiment 1) 45

4.35 VSWR Graph (Method 3: Experiment 1) 46

4.36 Removal of a Portion of the Right Patch (Experiment 2) 46

4.40 Removal of a Portion of the Left and Right Edges of the Patch

(Experiment 3) 47

4.44 Removal of a Portion of the Left and Right Edges of the Patch

(Experiment 4) 49

5.1 Magnitude Graph (Optimum Design) 53

5.2 VSWR Graph (Optimum Design) 54

5.3 Impedance Graph (Optimum Design) 54

5.4 Smith Chart (Optimum Design) 55

5.5 Dimension and Configuration of an Optimum 10 GHz Rectangular

Microstrip Patch Antenna 55

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CHAPTER 1

INTRODUCTION

1.1 Background

An important component in any radar or communication system is the antenna. Antennas play an important role in electromagnetic systems, for they form the only link between free-space and the system. In essence, an antenna is a component that converts a wave propagating on a transmission line to a plane wave propagating in free-space (transmission), or vice versa (reception) [3]. In a communications link, the microwave signal is radiated into space by an antenna at one end, and picked out of space by an antenna at the other end.

The same antenna may be acted as both the transmission and reception units.

From the most common use of antennas in household television transmission to radar systems such as airport surveillance, marine navigation, etc., the quality of antennas is undeniably the top consideration in the designing process. Apart from that, the various types of antennas that suit its

applications must also be taken into consideration.

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1.2 Basic Types of Antennas

How an antenna operate is very much dependent on the geometry of it. In other words, the physical structure and its orientation diversify the

characteristics of a typical antenna. Therefore, a wide variety of antenna types and geometries have been developed. The different types of antenna are such as [3]:

i. Wire antennas are the simplest types of antennas, and most of the earliest antennas (e. g., as used by Hertz and Marconi) were of this type. Wire antennas are easy to fabricate, easy to feed and are lightweight.

ii. Rod antennas. The diameter of the rod is significant. These antennas include whip antennas and dipoles of all descriptions.

iii. Aperture antennas are often just flared sections of waveguide, or even open-ended waveguides. Aperture antennas are most commonly used at microwave frequencies and have moderate gains.

iv. Printed antennas are a relatively new type of antenna comprising printed conductors on a microstrip or similar type of substrate. This makes them compatible with planar microwave circuit technology.

v. Reflector antennas achieve high gain by focusing the radiation from a small feed antenna with an electrically large reflector.

They are relatively easy to fabricate and are rugged, but can be large and impractical.

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1.3 Objectives

i. To design and simulate a 10 GHz rectangular microstrip patch antenna by using Microwave Office 2000.

ii. To learn more about the basic characteristics and operation of an antenna, and also the various parameters involved in designing the antenna.

iii. To learn antenna-designing software called Microwave Office 2000.

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CHAPTER 2

LI'T'ERATURE REVIEW

2.1 Microstrip 't'ransmission Line

A microstrip transmission line consists of a flat conducting strip suspended above the ground plane and being open on the top surface. The open structure means that the electromagnetic field is not confined to the solid dielectric, but is partly in the air space. The conducting strip is supported by a dielectric substrate. An example of a microstrip transmission line is shown in Figure 2.1 below 15 1.

COPPER STRIP DIELECTRIC

MATERIAL

CONDUCTING GROUND PLANE

Figure 2. 1 l hlirrnslrip Trunsniissionn Line

2.2 Characteristics Impedance of Nlicrostrip Lines

The characteristics impedance of a microstrip line is a function of the strip- line width, the strip-line thickness, the distance between the line and the ground the ground plane, and the homogeneous dielectric constant of the

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board material. Several different methods for determining the characteristic impedance of a microstrip line have been developed.

The better-known equation of the characteristic impedance of a wire-over-

ground transmission line is given by [3]: -

60 In [;

8d + W

JEC w 4d for W/d 51

12011 for W/d z 1

4Ee [W/d + 1.393 + 0.6671n (W/d + 1.444)]

where E = effective dielectric constant W = the width of the microstrip line

d = the height of the dielectric material

2.3 Dielectric Substrate

A range of substrate materials is available in the market, but for production runs alumina is the most widely used material, for frequencies up to about 20 GHz. At higher frequencies, quartz and sometimes sapphire, is used.

Dielectric constant, loss tangent and the variation with frequency and temperature, homogeneity, and isotropicity are the substrate properties that have to be considered in choosing the desired dielectric substrate.

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2.3.1 Dielectric Constant, e

The dielectric constant is the relative permitivity (c) of a material. It is dimensionless and always greater than 1. A dielectric constant of "1"

is equivalent to the permitivity of a vacuum, which is a fundamental constant (associated with the speed of light). In other words, vacuum has the lowest possible permitivity [7].

Good substrates have dielectric constant tolerances of a few percent or less, but the real problem is caused by variations in permitivity across the substrate, which can be as high as 0.5 to 1 %, especially for high permitivity substrates. The higher the permitivity, the more the energy will be reflected inside the antenna before leaving it, and the more inferior and narrow-banded the antenna will get [7].

Microstrip circuits were originally confined to lower frequency applications (such as VHF or UHF) because of the apparently uncontrolled radiation, which took place at microwave frequencies.

This characteristic was overcome when closely controlled high dielectric constant ceramic substrates became available and radiation was reduced to a tolerable level. Circuit patterns and ground planes are usually deposited on the substrates using thin-film or thick-film techniques.

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NG NfENC I TANN UNIVERSITI MALAYSIA SARAWAK 2002

SIMULATION 011 A 10 GIIZ RECTANGULAR MICROSrIRIP PATCH ANTENNA

Using MicroWave Office 2000

SEKSYEN 2, WANGSA MAJU. 53300 KUALA LUMPUR.

SUPERVISOR'S CERTIFICATION

SIMULATION OF A 10 GHZ RECTANGULAR MICROSTRIP PATCH ANTENNA USING MICROWAVE OFFICE 2000

NG MENG HANN

ABSTRACT

TABLE OF CONTENTS

CHAPTERS NO. CONTENTS

LIST OF FIGURES

THREE

REFERENCES BIBLIOGRAPHY APPENDIX

LIST OF TABLES

CHAPTER 1

1.2 Basic Types of Antennas

v. Reflector antennas achieve high gain by focusing the radiation from a small feed antenna with an electrically large reflector.

iii. To learn antenna-designing software called Microwave Office 2000.

CHAPTER 2

board material. Several different methods for determining the characteristic impedance of a microstrip line have been developed.

2.3.1 Dielectric Constant, e