development of microstrip patch array (wlan)...
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DEVELOPMENT OF MICROSTRIP PATCH ARRAY ANTENNA FOR WIRELESS LOCAL AREA NETWORK
(WLAN)
AZIZAN BIN MAT HASHIM
SCHOOL OF COMPUTER AND COMMUNICATION ENGINEERING
UNIVERSITI MALAYSIA PERLIS MALAYSIA
2007
DEVELOPMENT OF MICROSTRIP PATCH ARRAY ANTENNA FOR WIRELESS LOCAL AREA
NETWORK (WLAN)
by
AZIZAN BIN MAT HASHIM
Report submitted in partial fulfillment of the requirements for the degree
of Bachelor of Communication Engineering
MAY 2007
To my beloved mother:
Thank you for your understanding and giving me the chance to be what I can be.
ACKNOWLEDGEMENTS
I wish to express my thankfulness and my sincere appreciation to my supervisor Mr.
Amir Razif Arief Jamil Abdullah for his invaluable guidance, patience and support through
the completion of this final year project.
My deeply gratitude to Mr. Azremi Abdullah Al- Hadi and Mr. Soh Ping Jack for
their help and guidance during accomplish this project until successful. Not to forget to all
my friends those also help me in order to accomplish my project.
Thank you so much to my beloved family especially my mother, Habsah Saad for
your kind of understanding and moral support that never ending to me during carry out this
final year project.
Finally, I would like to thank again to everyone that has been involved in this
project directly or indirectly for their help and contribution.
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APPROVAL AND DECLARATION SHEET
This project report titled Developments of Microstrip Patch Array Antenna for Wireless Local Area Network (WLAN) was prepared and submitted by Azizan Mat Hashim (Matrix Number: 031080626) and has been found satisfactory in terms of scope, quality and presentation as partial fulfillment of the requirement for the Bachelor of Engineering (Communication Engineering) in Universiti Malaysia Perlis (UniMAP).
Checked and Approved by
_______________________
(AMIR RAZIF ARIEF JAMIL ABDULLAH) Project Supervisor
School of Computer and Communication Engineering Universiti Malaysia Perlis
May 2007
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DEVELOPMENT OF MICROSTRIP PATCH ARRAY ANTENNA FOR WIRELESS LOCAL AREA NETWORK (WLAN)
ABSTRACT
In this project, a 4x1 Rectangular Microstrip Patch Array Antenna at frequency 2.45 GHz
for Wireless Local Area Network (WLAN) will be designed, fabricated and tested. The
antenna will be design base on optimization and characteristics analysis. Some methods for
optimize the Microstrip Patch Antenna are studied and implemented to produce the desired
antenna. The objective of this project is to develop the antenna that has higher gain, higher
directivity, wide bandwidth and higher efficiency. Theoretically, the objective of this
project can be achieve through the use of high quality substrate such as RT Duroid 5870
which is have low relative permittivity or dielectric constant and higher substrate that will
improve the bandwidth. This is due to the Rectangular Microstrip Patch Array Antenna
which the bandwidth is determined by the dielectric constant and the height of substrate.
Low loss-tangent will increase the efficiency of the antenna. The patch array also has a
better directivity than the single patch. Microwave Office (MWO) will be introduce as an
effective tool for modeling electromagnetic structure. The antenna was fabricated based on
simulation and measured using Wave and Antenna Training System (WATS2002). The
expected result from this project is the antenna will has a high gain, better directivity, larger
bandwidth and high efficiency.
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PEMBANGUNAN ANTENNA SUSUNAN TAMPAL MIKROJALUR UNTUK RANGKAIAN TEMPATAN TANPA WAYAR (WLAN)
ABSTRAK
Di dalam projek ini, 4x1 Antena Susunan Tampal Mikrojalur Segiempat Tepat yang
beroperasi pada frekuensi kendalian 2.45 GHz yang digunakan untuk rangkaian tempatan
tanpa wayar akan direkabentuk, difabrikasi dan diuji. Antenna ini akan direkabentuk untuk
mengoptimakan prestasi dan ciri-cirinya akan dianalisis. Beberapa kaedah untuk
meengoptimumkan prestasi antena dikaji dan dipraktikkan. Objektif projek ini adalah
untuk menghasilkan antenna yang mempunyai gandaan, kearahan, lebarjalur dan
kecekapan yang tinggi. Secara teori, objektif projek ini dapat dicapai melalui penggunaan
substrat berkualiti tinggi seperti RT Duroid 5870 yang mempunyai pemalar dielektrik dan
ketinggian subtrat yang tinggi untuk menhasilkan lebarjalur yang lebih luas. Ini adalah
kerana bagi Antena Tampal Mikrojalur Segiempat Tepat, lebarjalur adalah bergantung
kepada pemalar dielektrik dan ketinggian substrat. Kehilangan tangen yang rendah dapat
meningkatkan kecekapan antenna. Perisian Microwave Office (MWO) diperkenalkan dan
digunakan untuk tujuan simulasi yang mana ianya merupakan perisian yang efektif untuk
permodelan struktur elektromagnet khususnya mikrojalur. Antena ini telah difabrikasi
berdasarkan kepada simulasi dan diuji menggunakan peralatan Sistem Latihan Antenna
dan Gelombang (WATS 2002). Daripada projek ini, hasil yang dharapkan adalah
membangunkan antenna yang mempunyai gandaan yang tinggi, kearahan yang lebih baik,
lebarjalur yang lebih luas dan kecekapan yang tinggi.
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TABLES OF CONTENTS
Page
DEDICATION i
ACKNOWLEDGEMENT ii
APPROVAL AND DECLARATION SHEET iii
ABSTRACT iv
ABSTRAK v
TABLE OF CONTENTS vi
LIST OF TABLES xi
LIST OF FIGURES xii
LIST OF SYMBOLS
xvii
CHAPTER 1 INTRODUCTION
1.1 Introduction
1.2 Objectives and Scope
1.3 Project Introduction
1.4 Array Elements
1.5 Project Implementation Strategy
1.6 Dissertation Overview
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CHAPTER 2 LITERATURE REVIEW
2.1 Introduction
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2.2 Research Paper Literature Review
2.2.1 Design of a Multi-layer Transmit / Receive Dual-Frequency
Microstrip Patch Antenna Array
2.2.2 New Considerations in the Design of Microstrip Antennas
2.2.3 Microstrip Patch Antenna Receiving Array Operating in the Ku
Band
2.2.4 Microstrip Antenna with Parasitic Elements
2.2.5 Guidelines for Design of Electromagnetically Coupled
Microstrip Patch Antennas on Two-Layer Substrates
2.2.6 High-Gain Microstrip Patch Array Antenna Using a
Superstrate Layer
2.2.7 Planar Square and Diamond Microstrip Patch Array
Antennas for Dual-Polarization Operation
2.3 Basic Antenna Theory
2.4 Antenna Properties
2.4.1 Impedance
2.4.2 VSWR
2.4.3 Bandwidth
2.4.4 Radiation Pattern
2.4.5 Gain
2.4.6 Polarization
2.5 Microstrip Patch Antenna
2.5.1 Introduction to Microstrip Patch Antenna
2.5.2 Operation of Microstrip Antenna
2.5.3 Shape of Microstrip Antenna
2.6 Factors Affecting Microstrip Design
2.6.1 Microstrip Discontinuity
2.6.1.1 Open End
2.6.1.2 Microstrip Line Step Discontinuity
2.6.1.3 Right Angle Bends
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2.6.2 Fringing Field
2.6.3 Feeding Techniques
2.6.3.1 Coaxial Probe Feed
2.6.3.2 Aperture Coupling
2.6.3.3 Proximity Coupling
2.6.3.4 Microstrip Line Feed
2.6.4 Substrate Selection
2.6.5 Patch Dimensions
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CHAPTER 3 DESIGN OF MICROSTRIP PATCH ARRAY ANTENNA
3.1 Introduction
3.2 Design Specifications
3.3 Single Microstrip Patch Antenna Design
3.3.1 Patch Calculations
3.3.1.1 Calculation of Patch Dimension
3.3.1.2 Calculation Of The Impedance For Quarter-Wave
Transformer
3.3.2 Quarter-Wave Transformer and 50 Ω Feedline Calculations
3.3.3 Radiation Pattern Calculation
3.4 Microstrip Patch Array Antenna Design
3.4.1 Array Calculation
3.4.1.1 Patch Calculation
3.4.1.2 Calculation Of The Impedance For Quarter-Wave
Transformer
3.4.2 50 Ω, 70 Ω and 100 Ω Transmission Line Calculation
3.4.3 Radiation Pattern Calculation
3.5 Introduction to Microwave Office
3.5.1 Layout Based Simulation
3.5.2 Radiation Pattern Generation
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Page
CHAPTER 4 RESULTS AND DISCUSSION
4.1 Introduction
4.1 Characteristics of Designed Antennas
4.3 Single Patch Microstrip Antenna
4.3.1 Microwave Office Simulation
4.3.1.1 Optimization of Patch Antenna
4.3.1.2 Radiation Pattern Simulation Result
4.3.2 Measurement Results
4.3.2.1 S11 Measurement
4.3.2.2 Radiation Pattern Measurement
4.3.2.3 NetStumbler Test
4.4 Microstrip Patch Array Antenna
4.4.1 Microwave Office Simulation
4.4.1.1 Optimization of Array Antenna
4.4.1.2 Radiation Pattern Simulation Result
4.4.2 Measurement Result
4.4.2.1 S11 Measurement
4.4.2.2 Radiation Pattern Measurement
4.4.2.3 NetStumbler Test
4.5 Discussion
4.5.1 S11 Response
4.5.2 Radiation Pattern.
4.5.3 NetStumbler Result
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CHAPTER 5 CONCLUSION
5.1 Introduction
5.2 Conclusion
5.3 Recommendation of Future Work
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Page
REFERENCES
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APPENDICES
Appendix A
Appendix A(i)
Appendix B
Appendix C
Appendix D
Appendix E
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LIST OF TABLES
Tables No. Page
2.0 Common Substrate Materials for Microstrip Antenna
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3.0 Single Patch Antenna Design Specifications
28
3.1
Dimension of Rectangular Patch Antenna 34
3.2 Dimension of Rectangular Patch Array Antenna
40
4.0
Various Dimension Effect on S11 Response 59
4.1
Optimise Dimension Versus Original Dimension (Single Patch) 59
4.2 Optimise Dimension Versus Original Dimension (Array Patch)
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4.3 Summarization of the Single Patch Antenna
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4.4 Summarization of the Array Patch Antenna
77
4.5 Summarization of the Radiation Pattern
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LIST OF FIGURES
Figures No. Page
1.0 Flow Chart of the Project
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2.0 2 X 2 Dual-Polarized Sub-arrays
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2.1 Frequency Response for the Antenna
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2.2 Radiation Pattern and 3dB Beamwidth
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2.3 Rectangular Microstrip Patch Antenna
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2.4 Circular Patch Antenna
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2.5 Open End Equivalent Circuit
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2.6 Open End Equivalent Circuit
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2.7 Equivalent Circuit for Bend
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2.8 Top View of Patch and a Demonstration of the Electric Fringing Fields that is Responsible for Radiation
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2.9 A Side View Of Microstrip Patch Antenna and the Demonstrating the Electric Fringing Fields
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Page
3.0 Patch Antenna with Quarter-Wave Transformer
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3.1
Screenshot of the Txline Calculator 33
3.2 Single Patch Antenna Design Layout
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3.3 Example of Series Feed
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3.4 One Dimension Parallel Feed Network
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3.5 Four Elements Array Line Impedance Design Layout
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3.6 Design Layout of Array Antenna
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3.7
The Microwave Office Welcome Page 41
3.8
The Circuit Schematic Based Environment 42
3.9 The Layout Schematic Based Environment
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3.10 The Substrate Information Option Window (Enclosure Tab)
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3.11
The Substrate Information Option Window (Dielectric Tab) 45
3.12 The Substrate Information Option Window (Boundaries Tab)
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3.13 The Rectangular Conductor Button Located At the Top Toolbar Used For Initial Drawing and Sizing
47
3.14 The Create Graph Pop-Up Window Option Indicating Types of Graphs
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Page
3.15 The Add Measurement Option Window
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3.16 The Project Options Option Window
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3.17
Add Measurement Option Windows When Adding PPC_Ephi and PPC_Etheta
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3.18
Exporting the Existing EM Structure 52
3.19 Re-Importing the Existing EM Structure
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3.20
The Options Window (Frequencies Tab) 53
3.21 Selecting the E-Field Settings Option
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3.22 Checking the Layer 1 Check Box So That E-Field Is Computed For That Layer
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3.23 The Analyze Button and Simulation Process Window
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4.0
S11 Simulation Response for Original Single Patch Dimension 58
4.1
Optimize S Simulated Response 11 60
4.2 Single Patch Optimized Radiation Pattern
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4.3 S11 Measurement Process Using Agilent E5062A Network Analyzer
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4.4 Measured S11 Result
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4.5
4.6
Single Patch Antenna Measurement Setup
Measured Single Patch Radiation Pattern
Page
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4.7 Wireless Router Setup for NetStumbler Test
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4.8 Single Patch Antenna NetStumbler Test Configuration
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4.9 Single Patch Antenna NetStumbler Test Result
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4.10 Simulated S Response for Original Array Antenna Dimensions
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4.11 Optimize S Array Antenna Response 11
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4.12 Optimized Simulated Radiation Pattern
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4.13
Measured S11 Response for Array Antenna
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4.14 S11 Measurement Process for Array Antenna Using Agilent E5062A Network Analyzer
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4.15 Radiation Pattern Measurement Setup for Array Antenna
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4.16 Measured Radiation Pattern for Array Antenna
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4.17 Wireless Router Setup for Array Antenna
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4.18 Microstrip Patch Array Antenna NetStumbler Testing Configuration
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Page
4.19 SNR versus Time for Patch Array Antenna
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4.20 Single Patch Antenna S11 Response Simulation versus Measurement
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4.21 Array Antenna S Response Simulation versus Measurement 11
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4.22 Comparison of Cell Size Effect for Simulation
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4.23 Comparison of SNR between Single Patch and Array Antenna
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LIST OF SYMBOLS, ABBREVIATIONS OR NOMENCLATURE
c Velocity of electromagnetic waves in free space
BW Bandwidth
HPBW Half Power Bandwidth
f Frequency
L Length of the Microstrip Patch Antenna
w Width of the Microstrip Patch Antenna
h Substrate thickness
Q Quality factor
t Thickness of conductor
tan δ Loss tangent of dielectric material
V voltage
G Gain
E Electric field
ρ Charge Density
inZ Input impedance
outZ Output Impedance
1Z Quarterwave (λ/4) Transformer Impedance
0Z Characteristic Impedance (Real) of the Input Transmission Line
εr Relative Permittivity
εeff Effective Relative Permittivity
f0 Resonant Frequency, Operating Frequency
ΔL Fringe factor
inR Resistance at the edge of the patch
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π A constant (=3.1416)
Ω Ohms
VSWR Voltage Standing Wave Ratio
f/b Front to back ratio
σ Conductivity
θ Angle
S S-Parameter that represented an input reflection 11
° Degree
SNR Signal to Noise Power Ratio
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