Slot Ultra Wideband (UWB) Antenna.
SLOT ULTRA WIDEBAND (UWB) ANTENNA
MUSFIRAH BT HILMI
This report is submitted in partial fulfillment of the requirements for the award of Bachelor of Electronic Engineering (Telecommunication Electronics) With Honours
Faculty of Electronic and Computer Engineering Universiti Teknikal Malaysia Melaka
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UNIVERSTI TEKNIKAL MALAYSIA MELAKA
FAKULTI KEJURUTERAAN ELEKTRONIK DAN KEJURUTERAAN KOMPUTER
BORANG PENGESAHAN STATUS LAPORAN
PROJEK SARJANA MUDA II
Tajuk Projek : SLOT ULTRA WIDEBAND (UWB) ANTENNA Sesi
Pengajian : 2008/2009
Saya MUSFIRAH BINTI HILMI
mengaku membenarkan Laporan Projek Sarjana Muda ini disimpan di Perpustakaan dengan syarat-syarat kegunaan seperti berikut:
1. Laporan adalah hakmilik Universiti Teknikal Malaysia Melaka.
2. Perpustakaan dibenarkan membuat salinan untuk tujuan pengajian sahaja.
3. Perpustakaan dibenarkan membuat salinan laporan ini sebagai bahan pertukaran antara institusi pengajian tinggi.
4. Sila tandakan ( √ ) :
SULIT*
(Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia seperti yang termaktub di dalam AKTA RAHSIA RASMI 1972)
TERHAD* (Mengandungi maklumat terhad yang telah ditentukan oleh
organisasi/badan di mana penyelidikan dijalankan)
TIDAK TERHAD
Disahkan oleh:
__________________________ ___________________________________
(TANDATANGAN PENULIS) (COP DAN TANDATANGAN PENYELIA)
Alamat Tetap:
49 JALAN USJ 4/6G
47600 SUBANG JAYA
Tarikh: ………. Tarikh: ………..
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“I hereby declare that this report is the result of my own work except for quotes as cited in the references.”
Signature :………. Author : MUSFIRAH BINTI HILMI
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“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 :……….
Supervisor’s Name :MOHAMAD ZOINOL ABIDIN ABD AZIZ Date :……….
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ACKNOWLEDGEMENT
First of all, praise to Allah for the goods and bless me along to complete this Final Year Project. I would like to thank all my lecturers involved especially my supervisor for their guidance as the approval notification for me to undergo my Final Year Project in Universiti Teknikal Malaysia Melaka (UTeM). Next, I would like to express my deepest gratitude to my colleagues for their continuous help, support, and guidance throughout this course in order to complete my project. I would also like to take this opportunity to thank again my supervisor Mr. Mohamad Zoinol Bin Abd Aziz whom had actually provided me with all the valuable, precious information to complete this report. Finally yet importantly, I would like to thank all for providing me a full cooperation whether direct or indirectly to me while undergoing this Final Year Project.
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ABSTRACT
Since the release by the Federal Communications Commission (FCC) of a bandwidth of 7.5 GHz (from 3.1 GHz to 10.6 GHz) for ultra wideband (UWB) wireless communications, UWB is rapidly advancing as a high data rate wireless communication technology. Due to the requirements of large capacity of data and high speed data transmission rate, UWB technology has become the promising communication system. There are many types of UWB antenna such as dipole, bow-tie, TEM horn, slot UWB antenna, planar antenna and array antenna. This project presents the design of a planar slot UWB antenna. The design is based on the slot UWB antenna by using a planar structure and designed for a frequency of 3.1 GHz to 10.6 GHz. The UWB antenna is achieved by applying parameter analysis in the design process. The slot UWB antenna design is simulated on Computer Simulation Technology (CST) Microwave Studio Software and fabricated on Flame Resistant 4 (FR4) substrate by using chemical etching techniques. The antenna achieved an absolute bandwidth of 7.2GHz with return loss -25dB. An average gain obtained from simulation is within the range from 2dB to 5.3dB.
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ABSTRAK
Sejak Suruhanjaya Komunikasi Persekutuan (FCC) melancarkan jalur lebar berfrekuensi 7.5 GHz (dari 3.1 GHz hingga 10.6 GHz), untuk komunikasi wayarles
“Ultra Wideband (UWB)” , UWB berkembang dengan pantas sebagai kadar data tinggi
dalam komunikasi wayarles teknologi. UWB teknologi menjadi keperluan dalam sistem komunikasi disebabkan oleh permintaan yang tinggi untuk kapasiti data yang besar serta kadar penghantaran yang mempunyai kelajuan yang tinggi. Terdapat beberapa jenis antena UWB seperti antena dwikutub, bow-tie, TEM horn, slot antena UWB, antenna
planar dan array. Projek ini bertujuan membina slot antena UWB. UWB antenna
diperolehi melalui analisis parameter semasa proses rekaan. Antena tersebut disimulasi menggunakan program Computer Simulation Technology (CST). Setelah proses simulasi selesai, antena difabrikasi pada papan substratum Flame Resistant 4 (FR4) dengan menggunakan proses goresan. Antena tersebut mencapai jalur lebar 7.2GHz dengan kehilangan balikan -25dB. Purata kenaikan yang diperolehi melalui simulasi adalah antara 2dB hingga 5.3dB.
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TABLE OF CONTENT
CHAPTER
I
TITLE
PROJECT TITLE
THESIS STATUS DECLARATION RESEARCHER’S DECLARATION SUPERVISOR’S DECLARATION DEDICATION
ACKNOWLEDGEMENT ABSTRACT
ABSTRAK
TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES
LIST OF ABBREVIATIONS LIST OF APPENDICES
INTRODUCTION
1.1 Introduction 1.2 Objectives
1.3 Problem Statement 1.4 Scope Of Work 1.5 Methodology
PAGE
i ii iii iv v vi vii viii ix xiii xiv xvii xix
1 3 3 3 4
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x
II BACKGROUND STUDY
2.1 Introduction to Ultra Wideband (UWB) 2.1.1 Background
2.2 Antenna Theory
2.2.1 Parameters of an Antenna 2.2.1.1 Radiation Pattern 2.2.1.2 Directivity 2.2.1.3 Gain
2.2.1.4 Frequency Bandwidth 2.2.2 Requirements for UWB antenna 2.3 Coplanar Waveguide (CPW)
2.3.1 History of coplanar waveguide 2.3.2 Types of coplanar waveguide
2.3.2.1 Coplanar Waveguide
2.3.2.2 Grounded Coplanar Waveguide 2.3.3 Advantages and disadvantages of coplanar waveguide
2.4 Types of Slot Ultra Wideband (UWB) Antenna Reviewed
2.4.1 Coplanar Waveguide-Fed Rectangular Slot Antenna
2.4.2 Elliptical Slot Antenna 2.4.3 T Slots Antenna
2.4.4 Cross Slot Antenna with U-Shaped Tuning Stub 2.4.5 Circular and Elliptical CPW-Fed Slot Antenna 2.4.6 Microstrip-Line-Fed Printed Planar Slot Antenna 2.4.7 Microstrip Square-Ring Slot Antenna
2.4.8 CPW-Fed Rectangular Slot Antenna with Tuning
6 6 8 9 9 11 12 12 13 15 15 15 15 16 16 17 17 18 19 20 20 21 22 22
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III
IV
Stub
2.4.9 Microstrip Square-Ring Slot Antenna Filled by an H-Shape Slot
2.4.10Rectangular Slot Antenna with Patch Stub
SLOT ULTRA WIDEBAND (UWB) ANTENNA
3.1 Introduction 3.2 Antenna Geometry
3.2.1 Parameter Analysis 3.2.1.1 Rectangular Slot 3.2.1.2 U-shaped stub
3.2.1.3 Center Conductor Width, Wf
3.2.1.4 Slot Width, WS
3.2.1.5 Width, A
3.2.1.6 Distance Between Slot and U-shaped, B
3.2.1.7 Width, C
3.2.2 Optimal Dimension of Design I
3.2.3 Adding Element at the Center of the Slot 3.2.4 Different Shape of Slot Antenna
3.3 Fabrication
3.4 Measurement Setup
RESULT ANALYSIS AND DISCUSSION
4.1 Parameter Analysis Result
4.1.1 Effect of the rectangular slot 4.1.2 Effect of the U-shaped stub
4.1.3 Effect of the center conductor width, Wf
23 24 25 26 28 28 28 29 30 30 31 31 32 33 34 35 38 40 40 42 43
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V
4.1.4 Effect of the slot width, WS
4.1.5 Effect of the width, A
4.1.6 Effect of the distance between slot and U-shaped,
B
4.1.7 Effect of the width, C
4.1.8 Optimal Design after Alteration 4.2 Simulation Results
4.2.1 Return Loss and Frequency Bandwidth 4.2.2 Radiation Pattern
4.2.3 Antenna Gain and Directivity 4.3 Measured Result
4.3.1 Return Loss and Frequency Bandwidth 4.3.2 Radiation Pattern
4.3.3 Antenna Gain
CONCLUSION
5.1 Conclusion 5.2 Future Work
REFERENCES
APPENDICES
44 44 45
45 46 47 47 48 49 50 50 52 55
56 57
58
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LIST OF TABLES
TABLE
3.1 3.2 3.3 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8
TITLE
Dimension of rectangular slot antennas Optimal dimension for Design I
Optimal dimension of slot antennas
Simulated -10 dB bandwidth printed slot antennas Half Power Beamwidth
Antenna gains for Design I and Design II
Simulated -10 dB bandwidth printed slot antennas for Design I Simulated -10 dB bandwidth printed slot antennas for Design II Half Power Beamwidth for Design I
Half Power Beamwidth for Design II Antenna Gain for Design I and Design II
PAGES
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LIST OF FIGURES
FIGURE 1.1 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 2.11 2.12 2.13 2.14 TITLE
Flow Chart of Methodology Antenna as a transition device
Radiation lobes and beamwidths of an antenna pattern
Linear Plot Of Power Pattern And Its Associated Lobes And Beamwidths
Coplanar Waveguide
Grounded Coplanar Waveguide
Geometry of the CPW-Fed rectangular slot antenna (units in mm) Geometry of the printed elliptical slot antenna
Geometry and Coordinate System of the T Slots Antenna Geometry of the cross slot antenna
Geometry of the proposed CPW-fed slot antenna configuration Geometry of printed planar slot antenna
Geometry of the SSRSA antenna
Geometry of the rectangular slot antenna Geometry of the square-ring slot antenna
The geometry and parameters of the rectangular slot antenna with
PAGES 5 9 10 10 15 16 18 18 19 20 21 21 22 23 24
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xv 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 patch stub
Geometry of CPW fed of Design I
Return Loss Simulation Result for Rectangular Slot Antenna Alteration of the rectangular slot
Alteration of the U-shaped stub
Alteration of the center conductor width, Wf
Alteration of the slot width, Ws
Alteration of the width, A
Alteration of the length between slot and U-shaped, B
Alteration of the width, C
Geometry of the Antenna When Adding Elements Geometry of Design II
The Antenna Layout
Fabricated CPW-Fed Slot Antenna The Fabrication Process
Network Analyzer Setup Measurement Setup
Return Loss Simulation Result of rectangular slot for different length
Return Loss Simulation Result of rectangular slot for different width
Return Loss Simulation Result for different length of U-shaped stub
Return Loss Simulation Result for different width of U-shaped stub
Return Loss Simulation Result for different Wf
Return Loss Simulation Result for different Ws
Return Loss Simulation Result for different width, A of U-shaped stub
Return Loss Simulation Result for different length, B
Return Loss Simulation Result for different width, C
26 27 28 29 29 30 30 31 31 33 34 36 36 37 38 39 41 41 42 43 43 44 45 45 46
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4.10 4.11 4.12 4.13 4.14 4.15 4.16
Return Loss Simulation Result for optimal design Return Loss Simulation Result
Radiation Patterns Simulation Result Return Loss Simulation Result for Design I Return Loss Simulation Result for Design II Radiation patterns of Design I
Radiation patterns of Design II
46 47 48 50 51 53 54
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LIST OF ABBREVIATIONS
1G 2G 3G 4G A ABW AWGN B C CPW CPWG CST dB dBi FBW FCC FDTD FR4 GHz - - - - - - - - - - - - - - - - - - - First-generation Second-generation Third-generation Fourth-generation Width of Stub Absolute Bandwidth
Additive White Gaussian Noise Distance between slot and U-shaped Width of Stub
Coplanar Waveguide
Coplanar Waveguide with Ground Computer Simulation Technology Decibel
Decibel above isotropic Fractional Bandwidth
Federal Communications Commission Finite-difference Time-domain
Flame Resistant 4 Giga Hertz
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xviii GPS GSM IEEE ISM L MHz MIC mm MMIC MSRSA PCB SNR SRSA SSRSA UMTS UWB VSWR W Wf WS Wi-Fi WLAN WPAN - - - - - - - - - - - - - - - - - - - - - - -
Global Positioning System
Global System for Mobile Communication Institute of Electrical and Electronics Engineers Industrial Scientific and Medicine
Length Mega Hertz
Microwave Integrated Circuit millimeter
Monolithic Microwave Integrated Circuit Microstrip Square-Ring Slot Antenna Printed Circuit Board
Signal-to-Noise Ratio Square-Ring Slot Antenna Split Square Ring Slot Antenna
Universal Mobile Telecommunications System Ultra Wideband
Voltage Standing Wave Ratio Width
Center Conductor Width Slot Width
Wireless Fidelity
Wireless Local Area Network Wireless Personal Area Network
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LIST OF APPENDICES
APPENDIX
A B C D
TITLE
Advantages of UWB UWB applications Microstrip
Results for Adding Element at the Center of the Slot
PAGES
63 65 67 73
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CHAPTER I
INTRODUCTION
1.1Introduction
Ultra wideband (UWB) is currently receiving special attention in industry and academia. The technical improvements have also enabled a large number of new services to emerge. The first-generation (1G) mobile communication technology only allowed analogue voice communication while the second-generation (2G) technology realized digital voice communication. Currently, the third-generation (3G) technology can provide video telephony, internet access, video/music download services as well as digital voice services. In the near future, the fourth-generation (4G) technology will be able to provide on-demand high quality audio and video services, and other advanced services.
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2
In recent years, more interest has been put into wireless personal area network (WPAN) technology worldwide. The future WPAN aims to provide reliable wireless connections between computers, portable devices and consumer electronics within a short range. Furthermore, fast data storage and exchange between these devices will also be accomplished. This requires a data rate which is much higher than what can be achieved through currently existing wireless technologies [1].
The maximum achievable data rate or capacity for the ideal band-limited additive white Gaussian noise (AWGN) channel is related to the bandwidth and signal-to-noise ratio (SNR) by Shannon-Nyquist criterion [2], as shown in Equation 1.1.
.
where C denotes the maximum transmit data rate, B stands for the channel bandwidth.
Equation 1.1 indicates that the transmit data rate can be increased by increasing the bandwidth occupation or transmission power. However, the transmission power cannot be readily increased because many portable devices are battery powered and the potential interference should also be avoided. Thus, a large frequency bandwidth will be the solution to achieve high data rate.
On February 14, 2002, the Federal Communications Commission (FCC) of the United States adopted the First Report and Order that permitted the commercial operation of UWB technology. Since then, UWB technology has been regarded as one of the most promising wireless technologies that promises to revolutionize high data rate transmission and enables the personal area networking industry leading to new innovations and greater quality of services to the end users [3].
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3
1.2Objectives
The main objective of this project is to design and implement slot Ultra Wideband (UWB) antenna for UWB application. The UWB antenna should be capable of operating over an ultra wide bandwidth as allocated by the FCC with bandwidth requirement from 3.1GHz to 10.6GHz and return loss below than -10dB.
1.3Problem Statement
In recent years, there has been an increase in the demand of large capacity of data and high speed data transmission rate. The limited bandwidth for wireless communication system is a drawback for the requirement of large capacity of data rate [1]. Besides the demand for small size and compact profile antennas, broadband ones are often required in order to cover simultaneously several bands. UWB is rapidly advancing as a high data rate wireless communication technology [4]. A slot UWB antenna is designed to have a larger bandwidth with large capacity of data and high speed data transmission rate.
1.4Scope Of Work
The slot UWB antenna is designed by using planar slot structure and simulated by using CST software in order to obtain the return loss, frequency bandwidth, gain, directivity, and radiation pattern. Then the antenna is fabricated on FR4 board by using chemical etching technique. Finally, analysis has been done to compare between the simulation and the measurement result.
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4
1.5Methodology
This project involves five major phase as shown in Figure 1.1. Firstly, a literature review was carried out from various sources such as journals, articles, books, and technical reports on UWB antenna. All the basic parameters such as its shape, dimensions, and all the mathematical parameters like its return loss, wavelength, directivity, VSWR and etc is analyzed and comprehended.
Then, the slot UWB antenna is designed by using planar slot structure. The UWB antenna should be capable of operating over an ultra wide bandwidth from 3.1GHz to 10.6GHz.
The CST software implementation is studied to design the antenna. The design that has been made with all parameters attained is then simulated using CST to analyze the antenna performance in order to obtain the return loss, frequency bandwidth, gain, directivity, and radiation pattern. If the design is not achieved a good performance, the design is being altered or redesign.
The UWB antenna is then fabricated on FR4 board by using chemical etching technique to validate the simulated prediction. Lastly, the return loss, gain, radiation pattern and frequency bandwidth are measured. The simulation results are compared to measurement results.
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Figure 1.1 Flow Chart of Methodology
Literature Review
Design the antenna
Simulate using CST
Fabrication
Measurement
Writing report
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LIST OF APPENDICES
APPENDIX
A B C D
TITLE
Advantages of UWB UWB applications Microstrip
Results for Adding Element at the Center of the Slot
PAGES
63 65 67 73
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CHAPTER I
INTRODUCTION
1.1Introduction
Ultra wideband (UWB) is currently receiving special attention in industry and academia. The technical improvements have also enabled a large number of new
services to emerge. The first-generation (1G) mobile communication technology only
allowed analogue voice communication while the second-generation (2G) technology
realized digital voice communication. Currently, the third-generation (3G) technology
can provide video telephony, internet access, video/music download services as well as
digital voice services. In the near future, the fourth-generation (4G) technology will be
able to provide on-demand high quality audio and video services, and other advanced services.
(3)
2
In recent years, more interest has been put into wireless personal area network (WPAN) technology worldwide. The future WPAN aims to provide reliable wireless connections between computers, portable devices and consumer electronics within a short range. Furthermore, fast data storage and exchange between these devices will also be accomplished. This requires a data rate which is much higher than what can be achieved through currently existing wireless technologies [1].
The maximum achievable data rate or capacity for the ideal band-limited additive white Gaussian noise (AWGN) channel is related to the bandwidth and signal-to-noise ratio (SNR) by Shannon-Nyquist criterion [2], as shown in Equation 1.1.
.
where C denotes the maximum transmit data rate, B stands for the channel bandwidth.
Equation 1.1 indicates that the transmit data rate can be increased by increasing the bandwidth occupation or transmission power. However, the transmission power cannot be readily increased because many portable devices are battery powered and the potential interference should also be avoided. Thus, a large frequency bandwidth will be the solution to achieve high data rate.
On February 14, 2002, the Federal Communications Commission (FCC) of the United States adopted the First Report and Order that permitted the commercial operation of UWB technology. Since then, UWB technology has been regarded as one of the most promising wireless technologies that promises to revolutionize high data rate transmission and enables the personal area networking industry leading to new innovations and greater quality of services to the end users [3].
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1.2Objectives
The main objective of this project is to design and implement slot Ultra Wideband (UWB) antenna for UWB application. The UWB antenna should be capable of operating over an ultra wide bandwidth as allocated by the FCC with bandwidth requirement from 3.1GHz to 10.6GHz and return loss below than -10dB.
1.3Problem Statement
In recent years, there has been an increase in the demand of large capacity of data and high speed data transmission rate. The limited bandwidth for wireless communication system is a drawback for the requirement of large capacity of data rate [1]. Besides the demand for small size and compact profile antennas, broadband ones are often required in order to cover simultaneously several bands. UWB is rapidly advancing as a high data rate wireless communication technology [4]. A slot UWB antenna is designed to have a larger bandwidth with large capacity of data and high speed data transmission rate.
1.4Scope Of Work
The slot UWB antenna is designed by using planar slot structure and simulated by using CST software in order to obtain the return loss, frequency bandwidth, gain, directivity, and radiation pattern. Then the antenna is fabricated on FR4 board by using chemical etching technique. Finally, analysis has been done to compare between the simulation and the measurement result.
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4
1.5Methodology
This project involves five major phase as shown in Figure 1.1. Firstly, a literature review was carried out from various sources such as journals, articles, books, and technical reports on UWB antenna. All the basic parameters such as its shape, dimensions, and all the mathematical parameters like its return loss, wavelength, directivity, VSWR and etc is analyzed and comprehended.
Then, the slot UWB antenna is designed by using planar slot structure. The UWB antenna should be capable of operating over an ultra wide bandwidth from 3.1GHz to 10.6GHz.
The CST software implementation is studied to design the antenna. The design that has been made with all parameters attained is then simulated using CST to analyze the antenna performance in order to obtain the return loss, frequency bandwidth, gain, directivity, and radiation pattern. If the design is not achieved a good performance, the design is being altered or redesign.
The UWB antenna is then fabricated on FR4 board by using chemical etching technique to validate the simulated prediction. Lastly, the return loss, gain, radiation pattern and frequency bandwidth are measured. The simulation results are compared to measurement results.
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Figure 1.1 Flow Chart of Methodology Literature Review
Design the antenna
Simulate using CST
Fabrication
Measurement
Writing report