Microstrip Fractal Array Antenna

MICROSTRIP FRACTAL ARRAY ANTENNA

FATHIN AFIQAH BINTI GHAZALI

This report is submitted in partial fulfillment of the requirements for the award of Bachelor of Electronic (Telecommunication Electronics) With Honours

Faculty of Electronic and Computer Engineering Universiti Teknikal Malaysia Melaka

Tajuk Projek Sesi Pengajian

UNIVERSTI TEKNIKAL MALAYSIA MELAKA

F AKUL TI KEillRUTERAAN ELEKTRONIK DAN KEillRUTERAAN KOMPUTER

BORANGPENGESAHANSTATUSLAPORAN PROJEK SARJANA MUDA II

MICROSTRIP FRACTAL ARRAY ANTENNA 2009/2010

Saya FA THIN AFIQAH BINTI GHAZALI

mengaku membenarkan Laporan Projek Sarjana Muda ini disimpan di Perpustakaan dengan syarat-syarat kegunaan seperti berikut:

1. Laporan ada1ah hakmi1ik Universiti Teknikal Malaysia Melaka.

2. Perpustakaan dibenarkan membuat salinan untuk tujuan pengajian sahaja.

3. Perpustakaan dibenarkan membuat salinan laporan ini sebagai bahan pe1iukaran antara institusi pengajian tinggi. 4. Sila tandakan ( --J )

D

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[21

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

(Mengandungi maklumat terhad yang telah ditentukan oleh organisasilbadan di mana penyelidikan dijalankan)

Disahkan oleh:

(TANDATANGAN PENULIS) (COP DAN TANDA TANG AN PENYELIA)

ABO. SHUKUR BIN JA'AFAR

Alamat Tetap:

N0:3, LOT 36996, JALAN UTAMA, PUTRA NUSANTARA, KG.SG.MERAB ULU, BANDAR BARU BANGI, 43657, SELANGOR DARULEHSAN

Tarikh: 30 APRIL 2010

" K.etua ,labatan (Kej. Te!akomunikasi)

rakult1 KeJu:uteraan Elektronik Dan Jf.ejurut~raa~ Komputer

Umver~1t1 Tekn1kal Malaysia Melaka (UTeM) Karung Berkunci No 1752

_ Pejabat Pos Durian Tungga1

r6109, Durian Tunggal, Melaka.

"I hereby declare that this report is the result of my own work except for quotes as

cited in the references."

Signature

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: FA THIN AFIQAH BINTI GHAZALI

: 30 APRIL 2010

"I hereby declare that I have read this report and in my opinion this report is

sufficient in terms of the scope and quality for the award of Bachelor of Electronic

Engineering (Telecommunication Electronics) with Honours"

Signature : ...

~~···

Date : 30 APRIL 2010

Special gratitude to my family, friends and especially my supervisor,

En. Abd. Shukur Bin Ja'afar.

ACKNOWLEDGEMENT

Syukur Alhamdullilah to God for giving me the great patient and good health for me to go through and complete this final year project.

These final year project have been benefited from review by a number of people, who gave me generously of their time and expertise. The first person I would like to give my greatest thanks is my supervisor, En. Abd. Shukur Bin Ja’afar for his encouragement, help and patience for spending his time to taught me all the way from the beginning until the end of this project. With him as my supervisor, I can learn something new that so useable for me in future. His guidance and advice are so much I appreciate. I am glad to have an amazing supervisor like him.

Deepest thankful to my lovely parents, En. Ghazali Bin Hj. Darusalam and Pn. Normah Binti Hj.Idris for their pray, supportive, and guidance to me. Not forget to my siblings and friends for their help and kindness to me during the project session. Their help are well appreciated.

Finally, may God can repay all your help and kindness with blissfully ways.

ABSTRACT

This project is about an antenna which is electrical device designed to transmit or receive radio waves or, more generally, any electromagnetic waves. A microstrip antenna is chosen for this project because it is simple and inexpensive to fabricate using modern printed- circuit technology. Moreover, the frequencies band that used in this project is 2.4GHz and 5.0GHz which is the Industrial, Scientific and Medical (ISM) band. Both of these frequencies represent the Wireless Local Area Network (WLAN) application. The first step will be designing and simulation. The design and simulation will be done in the Microwave Office Software which is user-friendly software and easy to handle. The designing begin on the square patch single element of the antenna. Then, it will be shrinking in size by using the fractal geometries which is Minkowski Geometry. This fractal antenna will be arranged in array configurations for performance improvement. Array is the combination of a single element that can improve the problem in single element antenna which it can produce better gain and bandwidth. Besides that, this project will include fabrication which the measurement will be taken and compare with the simulation.

ABSTRAK

Projek ini ialah tentang satu antena yang peranti elektrik mereka untuk mengalirkan atau menerima gelombang radio atau, lebih umumnya, mana-mana gelombang elektromagnet. Antena mikrostrip dipilih untuk projek ini kerana ia mudah dan tidak mahal untuk memfabrikasi menggunakan moden printed- teknologi litar. Tambahan pula, jalur frekuensi-frekuensi yang menggunakan dalam projek ini ialah 2.4GHz dan 5.0GHz yang merupakan Jalur Industrial, Scientific dan Medical (ISM). Kedua-dua frekuensi ini adalah didalam aplikasi Rangkaian Kawasan Tempatan Tanpa Wayar (WLAN). Operasi pertama akan mereka bentuk dan simulasi. Reka bentuk dan simulasi akan dibuat dalam Microwave Office Software yang perisian ramah pengguna dan mudah mengendalikan. Rekaan bermula dalam faktor tunggal yang berbentuk segi empat sama antena yang akan mengecut pada saiz dengan menggunakan teknik pengecilan saiz yang dikenali sebagai Geometri Minkowski. Kemudian, pecahan antena ini akan diatur dalam konfigurasi-konfigurasi tatasusunan untuk perbaikan prestasi. Array adalah gabungan lebih dari satu antena yang membentuk sekelompok antena untuk mencapai suatu tujuan tertentu, misalnya gain yang lebih besar, atau suatu karakter pancar tertentu. Selain itu, projek ini akan difabrikasi untuk membuat perbandingan antara yang simulasi dan yang telah diukur secara benar.

CONTENTS

CHAPTER ITEM PAGE

PROJECT TITLE i

DECLARATION ii

DEDICATION iv

ACKNOWLEDGEMENT v

ABSTRACT vi

ABSTRAK vii

CONTENTS viii

LIST OF TABLES xii

LIST OF FIGURES xiii

LIST OF ABBREVIATIONS xvi

LIST OF APPENDIX xvii

I INTRODUCTION 1.1 Brief Technical Overview 1

1.1.1 Wireless Communication 2 1.1.1.1 IEEE 802.11a-1999 or 802.11a 2 1.1.1.2 IEEE 802.11b-1999 or 802.11b 3 1.1.1.3 IEEE 802.11g-2003 or 802.11g 3 1.2 Objectives Project 4

1.3 Problem Statement 4

1.3.1 Problem 4 1.3.2 Solution Overview 4

1.4 Scopes of Work 5

1.5 Project Methodology 5

1.5.1 Work Flow 6

1.6 Report Structure 7

II LITERATURE REVIEW

2.1 Introduction 8

2.2 Antenna Theory 9

2.2.1 Microstrip Antenna 9

2.2.2 Fractal Antenna 11

2.2.3 Array Antenna 12

2.2.3.1 Broadside Array 13

2.2.3.2 Ordinary End-Fire Array 14

2.2.3.3 Phased Array 15

2.2.3.4 Hansen-Woodyard End-Fire Array 15

2.3 ISM Band 15

2.4 Parameter of Antenna 16

2.4.1 Radiation Pattern 16

2.4.2 Power Gain 19

2.4.3 Directivity 19

2.4.4 Bandwidth 20

2.4.5 Polarization 21

2.5 Advantages and Disadvantages of Microstrip Antenna 22

2.6 Minkowski Geometry 23

III PROJECT METHODOLOGY

3.1 Project Methodology 26

3.1.1 Theoretical Development 28

3.1.2 Simulation 28

3.1.3 Physical Implementation 29

3.1.4 Experimental testing 29

3.2 Calculation in MATHCAD 29

3.2.1 Element Width and Length 30

3.2.1.1 Calculation Width and Length on 2.4GHz 32 3.2.1.2 Calculation Width and Length on 5.0GHz 35

3.2.2 Matching Section 37

3.2.2.1 Step on Matching 38

3.2.3 Calculation on 1st _{and 2}nd _{Iteration on each}

Iteration factor; 0.25, 0.5, 0.75 42

3.3 Designing in Microwave Office Software 44

3.4 Fabrication 47

IV RESULTS AND ANALYSIS

4.1 Simulation Results 49

4.1.1 Results on Return Loss for each of

Iteration Number 49

4.1.2 Summarize of Return Loss on each iteration

factor of Microstrip Patch Antenna 57 4.1.3 Graph on the Iteration Factor versus

Resonance Frequency 59

4.1.4 Graph of Size Reduction on each of

Iteration Factor at 2nd iteration number 60 4.1.5 Radiation Pattern for Microstrip Fractal

Array Antenna 64

4.1.6 Summarize of Radiation Pattern and Bandwidth of Microstrip Fractal Array Antenna 72

4.2 Fabrication Results 74

4.3 Discussions 76

V CONCLUSION AND FUTURE RECOMMENDATION

5.1 Conclusion 78

5.2 Future Work 79

REFERENCES 80

LIST OF TABLES

NO TITLE PAGE

3.1 Calculation on Minkowski Geometry at 2.4GHz 42

3.2 Calculation on Minkowski Geometry at 5.0GHz 43

4.1 Return Loss on each iteration at 2.4GHz 57

4.2 Return Loss on each iteration at 5.0GHz 58

4.3 Summary on radiation pattern and bandwidth at 2.4GHz 72 4.4 Summary on radiation pattern and bandwidth at 5.0GHz 73

LIST OF FIGURES

NO TITLE PAGE

2.1 (a) A rectangular microstrip antenna with a microstrip line feed

(b) An eight-element linear array of microstrip patches with a coplanar

microstrip feed network 10

2.2 From above of Microstrip Antenna 10

2.3 From side of Microstrip Antenna 11

2.4 The pattern of the conductor in fractal loop antennas 12

2.5 Broadside Arrays 14

2.6 2-D array 14

2.7 The radiation pattern form the side, above and 3-D 17

2.8 Radiation Pattern Lobes 18

2.9 Radiation Pattern Beamwidth 19

2.10 Measuring Bandwidth from Return Loss versus Frequency 21

2.11 Types of Polarization 22

2.12 Generation procedure for Minkowski fractal curve 24

2.13 Basic Calculation of Minkowski 24

3.1 Project expectation’s flow 27

3.2 Basic Construction Square Patch Antenna without Matching 32 3.3 Calculation on width and length for 2.4GHz in Mathcad 32 3.4 Calculation on width and length (Zo=50Ω) for 2.4GHz in Mathcad 33 3.5 Calculation on width and length for 5.0GHz in Mathcad 35 3.6 Calculation on width and length (Zo=50Ω) for 5.0GHz in Mathcad 36

3.7 Quarter-wave Matching Network 37

3.8 Square Patch Antenna with Matching 38

3.9 Calculation on Matching in Mathcad 38

3.10 Getting the characteristic impedance for 2.4GHz from simulation 39

3.11 Distance of Quarter-Wave Macthing 40

3.12 Set new EM structure 44

3.13 Set the element options for material 44

3.14 Set the element options for dielectric layers 45

3.15 Square patch antenna 45

3.16 1st _{iteration on 0.25 iteration factor 46}

3.17 2nd _{iteration on 0.25 iteration factor 46}

3.18 Fabrication Process 47

4.1 Square patch antenna at 2.4GHz 50

4.2 1st _{iteration at 2.4GHz (0.25 iteration factor) 50}

4.3 2nd _{iteration at 2.4GHz (0.25 iteration factor) 51}

4.4 1st _{iteration at 2.4GHz (0.5 iteration factor) 51}

4.5 2nd _{iteration at 2.4GHz (0.5 iteration factor) 52}

4.6 1st iteration at 2.4GHz (0.75 iteration factor) 52 4.7 2nd _{iteration at 2.4GHz (0.75 iteration factor) 53}

4.8 Square patch antenna at 5.0GHz 53

4.9 1st iteration at 5.0GHz (0.25 iteration factor) 54 4.10 2nd iteration at 5.0GHz (0.25 iteration factor) 54 4.11 1st iteration at 5.0GHz (0.5 iteration factor) 55 4.12 2nd _{iteration at 5.0GHz (0.5 iteration factor) 55}

4.13 1st _{iteration at 5.0GHz (0.75 iteration factor) 56}

4.14 2nd iteration at 5.0GHz (0.75 iteration factor) 56 4.15 Graph on iteration factor versus frequency at 2.4GHz 59 4.16 Graph on iteration factor versus frequency at 5.0GHz 59

4.17 Graph of size reduction at 2.4GHz 60

4.18 Resonance Frequency on the size reduction of antenna at 2.4GHz 61

4.19 Graph of size reduction at 5.0GHz 62

4.20 Resonance Frequency on the size reduction of antenna at 5.0GHz 63

4.21 0 iteration square patch array antenna at 2.4GHz 64

4.22 2nd _{iteration on 0.25 iteration factor fractal array antenna at 2.4GHz 65}

4.23 2nd _{iteration on 0.5 iteration factor fractal array antenna at 2.4GHz 66}

4.24 2nd iteration on 0.75 iteration factor fractal array antenna at 2.4GHz 67

4.25 0 iteration square patch array antenna at 5.0GHz 68

4.26 2nd _{iteration on 0.25 iteration factor fractal array antenna at 5.0GHz 69}

4.27 2nd _{iteration on 0.5 iteration factor fractal array antenna at 5.0GHz 70}

4.28 2nd _{iteration on 0.75 iteration factor fractal array antenna at 5.0GHz 71}

4.29 0.25 and 0.5 iteration factor microstrip fractal array antenna at 2.4GHz 74 4.30 0.5 and 0.75 iteration factor microstrip fractal array antenna at 5.0GHz 75

LIST OF ABBREVIATIONS

GPS Global Positioning System

ISM Band Industrial, Scientific, Medical Band

WLAN Wireless Local Area Network

IEEE Institute of Electrical and Electronics Engineering GSM Global Special Mobile (Cellular Phone)

MWO Microwave Office Software

dB Decibel

FEA Fractal Element Array

𝑙qw Length of Quarter-wave Matching

LIST OF APPENDIX

NO TITLE PAGE

A MathCad Datasheet 82

B Microwave Software 83

C Technical Report 84

D Calculation of Microstrip Fractal Array Antenna 85

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CHAPTER 1

INTRODUCTION

This chapter about the introduction of the project where it involves of the overview on this project, objectives, problem statements, scope, methodology, and report structure.

1.1 Brief Technical Overview

Microstrip antennas have been one of the most innovative topics in antenna theory and design in recent years, and are increasingly finding application in a wide range of modern microwave systems. Thus, it can be assemble by a thousand of designing with variety on application. Examples of application are, on the radar system, GPS and many of modern wireless communication equipment.

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Fractal shapes antenna had been discovered that it can radiate electromagnetic energy very well and have several properties that are advantageous over traditional antenna types.

Applying array on this microstrip antenna can improve the functionality of modern wireless communication receivers such as cellular handsets.

1.1.1 Wireless Communication

802.11 is a set of IEEE standards that govern wireless networking transmission methods. IEEE 802.11b and 802.11g using the same frequency which are 2.4 GHz but they are differ from IEEE 802.11b specification that extended throughput up to 11 Mbit/s and IEEE 802.11g specification that extended throughput to up to 54 Mbit/s. For the IEEE 802.11a specification that added a higher throughput of up to 54 Mbit/s and uses the 5 GHz band.

1.1.1.1 IEEE 802.11a-1999 or 802.11a

The IEEE 802.11a amendment to the original standard was ratified in 1999. It standard uses the same core protocol as the original standard, operates in 5 GHz band, and uses a 52-subcarrier orthogonal frequency-division multiplexing (OFDM) with a maximum raw data rate of 54 Mbit/s, which yields realistic net achievable throughput in the mid-20 Mbit/s.

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by walls and other solid objects in their path. On the other hand, OFDM has fundamental propagation advantages when in a high multipath environment, such as an indoor office, and the higher frequencies enable the building of smaller antennas with higher RF system gain which counteract the disadvantage of a higher band of operation. The increased number of usable channels (4 to 8 times as many in FCC countries) and the near absence of other interfering systems (microwave ovens, cordless phones, baby monitors) give 802.11a significant aggregate bandwidth and reliability advantages over 802.11b/g.

1.1.1.2 IEEE 802.11b-1999 or 802.11b

The IEEE 802.11b has a maximum raw data rate of 11 Mbit/s and uses the same CSMA/CA media access method defined in the original standard. 802.11b devices suffer interference from other products operating in the 2.4 GHz band. Devices operating in the 2.4 GHz range include: microwave ovens, Bluetooth devices, baby monitors and cordless telephones. Interference issues and user density problems within the 2.4 GHz band have become a major concern and frustration for users.

1.1.1.3 IEEE 802.11g-2003 or 802.11g

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the same frequency band as 802.11b, it can achieve higher data rates because of its heritage to 802.11a.

1.2 Objectives

The objectives of this project are:

 To design the microstrip fractal array antenna using 2.4GHz and 5.0GHz.

 To investigate the behaviour of the Minkowski antenna properties.

 To miniaturize a square patch antenna using Minkowski geometry.

 To compare the measurement taken from fabrication with the simulation.

1.3 Problem statement

1.3.1 Problem

As before, usually the antenna that been used were big size antenna with rectangular or circular shape. Nowadays, there are needs on a compact and small size antenna for the usage of certain application such as wireless application. However, to produce a compact antenna needs the minimization on the actual size antenna. The minimization is the problem that needs to be focus on.

1.3.2 Solution Overview

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fractal antenna is it can shrink in size by two or four time from the actual size by surprisingly maintaining the good performance.

1.4 Scopes of Work

1. Designing and simulation using the Microwave Office. 2. Fabrication.

3. Measurement.

4. Compare the simulation with the measurement.

1.5 Project Methodology

1. Literature review.

Previous project of the antenna is for the GPS and ISM band application. However, to upgrade the antenna project, frequency of 2.4GHz and 5.0GHz are applied. 2.4GHz band is the unlicensed band of IEEE 802.11b and 802.11g and 802.11a is the 5GHz unlicensed frequency band. Both of the frequency are the in the WLANs application.

2. Calculation of Minkowski.

Calculation will be carried out before designing in the Microwave Office. 3. Design and simulation using the Microwave Office.

In the Microwave Office, the designing and simulation with the process of array will take part.

4. Fabrication.

The fabrication will be done from the printed design. After that, the etching process will take part.

5. Comparison.

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1.5.1 Work Flow

Fabrication and Measure Calculation of Minkowski geometry

Analysis and report writing Literature Review

Analysis Expected results?

END Analysis

Expected results?

Yes No

Yes No

START

Design and simulate in the Microwave Office i) Design a square patch antenna

ii) Apply Minkowski geometry to square patch antenna

iii) Change important parameter, number of iteration and iteration factor

iv) Analyze data and do prediction on new

v) Design new Minkowski Antenna at specific operating frequency