MILLIMETER-WAVE GRID ARRAY ANTENNA FOR 5G MOBILE...

MILLIMETER-WAVE GRID ARRAY ANTENNA FOR 5G MOBILE

COMMUNICATION NETWORKS

ABU BAKR MOHAMED ALI MUSTAFA

UNIVERSITI TEKNOLOGI MALAYSIA

MILLIMETER-WAVE GRID ARRAY ANTENNA FOR 5G MOBILE

COMMUNICATION NETWORKS


A project report submitted in partial fulfilment of the

requirements for the award of the degree of

Master of Engineering (Electrical - Electronics & Telecommunication)

Faculty of Electrical Engineering

Universiti Teknologi Malaysia

JUNE 2015

iii

DEDICATION

Dedication to my beloved parents, my Brothers and my fiancée for their support and

care.

iv

ACKNOWLEDGEMENT

First and foremost, thanks God, for blessing me the strength to complete this

study. I would like to express my deepest appreciation to several people that helped

me during the course of my master’s program at Universiti Teknologi Malaysia.

A special gratitude I give to my supervisor, Associated Professor Ir. Dr.

Sharul Kamal Abdul Rahim, whose contribution in stimulating suggestions and

encouragement, helped me to coordinate my project especially in writing this master

project report. Without him this project report will not become a reality.

I am very grateful to my parents, for their endless prayers, love and

encouragement, not only during this master’s program, but also during all my life. I

wish to express my love and gratitude to other members of my family, especially my

brother Maaz and my fiancée Maha, for their supports and endless love, through the

duration of my studies.

Furthermore I would also like to acknowledge with much appreciation the

crucial role of the staff of Universiti Teknologi Malaysia, who gave the permission

to use all required equipment and the necessary materials to complete the task

“Antenna fabrication and measurements”.

Thanks all of you


v

ABSTRACT

A single feed grid array antenna for 28 GHz for 5G Mobile Communication

Networks is proposed. It is designed on 1.52 mm thick substrate made of Rogers

Duroid 5880LZ ( = 1.96 and tan δ = 0.0019) with 0.035 mm copper claddings.

Dimension of the antenna is 80 mm × 80 mm × 1.52 mm. The grid array antenna is

fed by a SSMA coaxial probe feed connector with Teflon ( =2.1) with inner

diameter p = 0.5 mm and outer diameter d = 2 mm, is drilled through the ground and

the substrate to feed the radiating element and to achieve the characteristic

impedance of 50 Ω. The measured antenna exhibits 2.6 % impedance bandwidth

from 27.576 to 28.312 GHz at 27.944 GHz with 1.74% 3dB impedance bandwidth of

27.724 to 28.212 GHz at 27.986 GHz. The simulated antenna exhibits 41 %

impedance bandwidth from 22 to 33.38 GHz at 27.694 GHz, and 10.3% 3dB

impedance bandwidth from 26.58 to 29.765 GHz at 28.1 GHz, and 15.2dB gain at 28

GHz, with a 3dB gain bandwidth from 25.159 to 31.192 GHz. The comparison

between simulation and measurement results indicate that good agreement between

measured and simulated results. The discrepancy between the measured and

simulated results may be due to the effects of the RF cable, the SSMA to SMA

adapter configurations and KEYSGHT N5234A PNA-L Microwave Network

Analyser calibration process.

vi

ABSTRAK

Sebuah grid pelbagai antena suapan tunggal bagi 28 GHz untuk 5G

rangkaian komunikasi mudah alih adalah dicadangkan. Ia direka pada 1.52 mm

substrat tebal diperbuat daripada Rogers Duroid 5880LZ (εr = 1.96 dan tan δ =

0,0019) dengan claddings tembaga 0,035 mm. Dimensi antena ialah 80 mm × 80 mm

× 1.52 mm. Antena tatasusunan grid disuap oleh SSMA sepaksi penyambung probe

dengan Teflon (εr = 2.1) dengan diameter dalaman p = 0.5 mm dan diameter luar d =

2 mm, digerudi melalui Tanah dan substrat untuk memberi makan elemen terpancar

dan mencapai galangan ciri 50 Ω. Antena diukur menunjukkan 2.6% impedans

bandwidth 27,576-28,312 GHz di 27,944 GHz dengan 1.74% 3dB impedans

bandwidth daripada 27,724-28,212 GHz di 27,986 GHz. Antena simulasi

menunjukkan 41% impedans bandwidth 22-33,38 GHz di 27,694 GHz, dan 10.3%

3dB impedans bandwidth 26,58-29,765 GHz pada 28.1 GHz, dan 15.2dB

keuntungan pada 28 GHz, dengan 3dB keuntungan bandwidth 25,159-31,192 GHz .

Perbandingan antara keputusan simulasi dan pengukuran menunjukkan bahawa

perjanjian yang baik antara keputusan diukur dan simulasi. Perbezaan antara

keputusan diukur dan simulasi mungkin disebabkan oleh kesan kabel RF, yang

SSMA untuk SMA konfigurasi dan penyesuai KEYSGHT N5234A PNA-L

Microwave Penganalisis Rangkaian proses penentukuran.

vii

TABLE OF CONTENTS

CHAPTER TITLE PAGE

DECLARATION II

DEDICATION III

ACKNOWLEDGEMENT IV

ABSTRACT V

ABSTRAK VI

TABLE OF CONTENTS VII

LIST OF TABLES IX

LIST OF FIGURES X

LIST OF ABBREVIATION XIII

LIST OF SYMBOLS XV

1 INTRODUCTION 1

1.1 Introduction 1

1.2 Problem Statement 2

1.3 Objectives of the Study 2

1.4 Scope of the Study 3

1.5 Thesis Outlines 3

2 LITERATURE REVIEW 5

2.1 Introduction 5

2.2 Evolution of the Grid array antenna 7

2.3 Principle of operation of microstrip grid-array antennas at

millimeter-wave frequencies 10

2.4 Analysis of the grid array antenna on a variety of substrates at

millimeter-wave frequencies. 18

2.4.1 Microstrip grid array antenna Resonant Frequency 20

viii

2.4.2 Microstrip grid array antenna Impedance bandwidth 22

2.4.3 Microstrip grid array antenna Half-Power Beam-width 24

2.4.4 Microstrip grid array antenna Gain 26

2.4.5 Microstrip grid array antenna Gain bandwidth 28

2.4.6 Microstrip grid array antenna Synthesis 30

2.5 Wideband and Compact Microstrip Grid Array Antenna 35

2.6 Microstrip Grid Array Antenna Excited by Capacitive Slot 38

2.7 Summary 40

3 RESEARCH METHODOLOGY 42

3.1 Introduction 42

3.2 Flow of project 42

3.3 Design parameters and specifications 45

3.4 Simulation Tool 45

3.5 Fabrication Process 46

3.6 Measurement Process 47

3.7 Summary 48

4 SIMULATION AND MEASUREMENT RESULTS 49

4.1 Introduction 49

4.2 Antenna Design 49

4.3 Simulation results 50

4.3.1 Parametric Study 51

4.3.2 Optimum simulation results 55

4.4 Fabricated Microstrip Grid Array Antenna 60

4.5 Fabricated antenna and Measurement results 60

4.6 Summary 61

5 CONCLUSION 63

5.1 Conclusion 63

5.2 Future Work 64

REFERENCES 66

Appendix A 69

ix

LIST OF TABLES

TABLE NO. TITLE PAGE

2.1 B. Zhang and Y. P. Zhang antenna design parameters 11

2.2 B. Zhang and Y. P. Zhang antenna design parameters 18

‎3.1 Shows the parameters and design specifications 45

3.2 Substrate specification 45

4.3 Symbols in Figure 4.4 & parameters 54

‎4.4 Antenna parameters 55

4.5 Radiation efficiency of the antenna according directivity and gain 56

4.1 Vs. Frequency for l=8 mm, 8.5 mm, 8.85 mm, 9 mm

respectively 69

4.2 Gain (dB) Vs. Frequency For l=8 mm, 8.5 mm, 8.85 mm, 9 mm

respectively 70

x

LIST OF FIGURES

FIGURE NO. TITLE PAGE

2.1 Rain attenuation in dB/km across frequency 6

2.2 Atmospheric absorption across millimeter waves frequencies 7

2.3 The configuration of a novel microstrip grid-array antenna

proposed by Nakano, who added two more shorts sides to make

an equal number of short sides (radiating elements) in both the

x and y directions [26] 10

2.4 The input impedance 12

2.5 The magnitude of 12

‎2.6 The peak realized gain as functions of frequency 13

2.7 The current distribution at the parallel resonance, 60 GHz 13

2.8 The E-plane patterns at the parallel resonance, 60 GHz 14

2.9 The H-plane patterns at the parallel resonance, 60 GHz 14

2.10 The current distribution at the series resonance, 57 GHz 15

‎2.11 E-plane patterns at the series resonance, 57 15

2.12 The H-plane patterns at the series resonance, 57 GHz . 16

2.13 The current distribution at non-resonance, 52 GHz 16

2.14 The E-plane patterns at non-resonance, 52 17

2.15 The H-plane patterns at non-resonance, 52 GHz 17

2.16 The resonant frequency as a function of the relative Permittivity for

fixed substrate thickness: 0.254 - mm (0.0508 ) 21

2.17 The resonant frequency as a function of the relative Permittivity

fixed substrate thickness: 0.381- mm (0.0762 ) 21

‎2.18 The resonant frequency as a function of the relative Permittivity for


‎2.19 The impedance bandwidth as a function of the relative Permittivity for


xi

2.20 The impedance bandwidth as a function of the relative Permittivity for


2.21 The impedance bandwidth as a function of the relative Permittivity for


2.22 The half-power bandwidth as a function of the relative permittivity for


‎2.23 The half-power bandwidth as a function of the relative permittivity for


2.24 The half-power bandwidth as a function of the relative permittivity for


‎2.25 The realized peak gain as a function of the relative permittivity for fixed

substrate thickness: 0.254 - mm (0.0508 ) 27

2.26 The realized peak gain as a function of the relative permittivity for fixed

substrate thickness: 0.381- mm (0.0762 ) 27

2.27 The realized peak gain as a function of the relative permittivity for fixed


‎2.28 The gain bandwidth as a function of the relative permittivity for fixed


2.29 The gain bandwidth as a function of the relative permittivity for fixed

substrate thickness: 0.381- mm (0.0762 ) 29

2.30 The gain bandwidth as a function of the relative permittivity for fixed


‎2.31 The radiation resistance as a function of the width of the short side for


‎2.32 The radiation resistance as a function of the width of the short side for


2.33 The radiation resistance as a function of the width of the short side for


2.34 The fabricated prototype antenna 37

2.35 The configuration of the microstrip grid array antenna 37

2.36 Microstrip grid array antenna 39

2.37 Zoom-in view of capacitive coupling slot 39

3.1 Stream of the entire project 44

3.2 CST studio suite environment 46

3.3 KEYSGHT N5234A PNA-L Microwave Network Analyzer, 43.5GHz 47

‎4.1 The geometry of the proposed antenna 50

xii

‎4.2 Effect of changing dimension l on return 51

‎4.3 Effect of changing dimension of l on the antenna Gain 51

4.4 Effect of changing dimension , on the return loss 54

4.5 Effect of changing dimension , on the antenna gain 55

4.6 Return loss of proposed antenna 56

4.7 Estimated gain of proposed antenna 57

4.8 Radiation efficiency of the proposed antenna 57

‎4.9 3D radiation pattern of proposed antenna at 28 GHz 58

4.10 Simulated H-plane at 28GHz 59

4.11 Simulated E-plane at 28GHz 59

4.12 The current distribution at the resonance, 28 GHz 59

‎4.13 Fabricated Proposed microstrip grid array antenna 60

‎4.14 Measured return loss of proposed antenna 61

‎5.1 Basic Antenna for future work 64

‎5.2 S-parameters for the antenna for future work 65

‎5.3 Peak realized gain for the antenna for future work 65

xiii

LIST OF ABBREVIATIONS

5G ˗ Fifth Generation

4G - Fourth Generation

LTE-A - Long Term Evolution Advanced

WiMAX - Worldwide interoperability for Microwave Access

MIMO - Multiple Input Multiple Output

MMIC - Monolithic Microwave Integrated Circuits

AiP - Antenna in Package

FCC - Federal Communication Commission

CPW - Coplanar Wave Guide

LTCC - Low Temperature Cofired Ceramic

MGAA - Microstrip Grid Array Antenna

MCAA - Microstrip Comb Array Antenna

VSWR - Voltage Standing Wave Ratio

HFSS - High Frequency Structural Simulator

CST - Computer Simulation Software

RFIC - Radio Frequency Integrated Circuit

dB - Decibel

BW - Bandwidth

Hz - Hertz

MHz - Mega Hertz

GHz - Giga Hertz

RF - Radio Frequency

mm - Millimeter

GA - Genetic Algorithm

Km - Kilometer

m - meter

xiv

dBi - decibels-isotropic

xv

LIST OF SYMBOLS

- Relative permittivity

- Effective permittivity

δ - Tangent loss

a - Substrate length

b - Substrate width

h - Substrate thickness

L - Length of the long side of the mesh

- Width of the long side of the mesh

S - Length of the short side of the mesh

- Width of the short side of the mesh

- Guided wave length

p - feeding-pin diameter

d - Aperture diameter

Ω - ohm

- reflection coefficient

| | - Magnitude of the reflection coefficient

- Wave length in free space

- Speed of light

- Frequency in free space

- characteristic impedance of the long side

- characteristic impedance of the short side

- radiation resistance

- empirical factor

- number of meshes

- minor axis length

- major axis length

xvi

- sinusoid lines width

- sinusoid lines length

- sinusoid lines amplitude

- number of periodicities in a section of a sinusoid line

- area reduction factor

CHAPTER 1

1 INTRODUCTION

1.1 Introduction

Today there is a variety of multimedia services arises with the evolution of

the mobile devices industry and raped development in the mobile communication

sector and the use of mobile communication at these days does not depend on voice

communication only it is include also broadband and multimedia services that the

mobile communication infrastructure can support, but on top of that there is always

a user demand for high mobility, high data rate and high availability with good

quality of service guarantee. All these user requirements push the mobile

communication industry for looking to a new technology and new frequency

spectrum to support their infrastructure to meet the user requirements.

Qualcomm expects that the mobile traffic in 2020 will be 1000 times more

than that of the current mobile traffic. To handle all of current mobile

communication traffic the (4G) mobile communication system, (LTE-A) long term

evolution advanced and (WiMAX) worldwide interoperability for microwave access

uses advanced technologies such as (MIMO) multiple input multiple output, carrier

aggregation and multicarrier transmission[1]. Also all that technologies, frequency

band from 3GHz and below used in recent mobile communication are expected to be

consumed due to the more demand in mobile communication data traffic. There for,

accommodate the new data traffic requirements and user demands the frequency

band should be enlarge, thus a new frequency band will be considered in (5G)

mobile communication systems. The band in the 30GHz – 300GHz range at

millimeter wave band is being considered as a good candidate for new mobile

2

communication system (5G)[2], thus the system capacity of (5G) mobile

communication system will be improved and mobile devices served by base station

can experience better service environment with high speed broadband transmission

with low latency when compared with the current mobile communication systems.

Therefore the use of millimeter wave band for (5G) mobile communication system

will provide novel multimedia services.

The transceivers in (5G) must guarantee a secure communication with

reliable link speed of Gigabit per second everywhere any time. Around all the

transceiver components for millimeter wave (30GHz – 300GHz) for (5G) mobile

communication the antenna design required significant changes. This is because all

the mobile communication standards up to (4G) has operate in the range of the

microwave spectrum 300MHz-3GHz.

1.2 Problem Statement

The development of 5G mobile communication networks focuses on

providing higher bandwidth and longer range. Thus the spectrum available in the

millimeter-wave frequency bands provides multi-gigabit-per second data rates, but

the realized communication range will be constrained based on several factors.

These incorporate the higher atmospheric attenuation at these frequencies,

furthermore the limited output power of monolithic microwave integrated circuits

(MMIC) due to physical constraints. Therefore, the performance of the mobile

millimeter-wave networks requires enhancement by using high gain antenna arrays.

1.3 Objectives of the Study

The objective of this project focus on design, simulate and fabricate a

microstrip grid array antenna at millimeter-wave frequencies for (5G) mobile

communications with an operating frequency of 28GHz, Moreover the proposed

3

microstrip grid array antenna must provide a high gain and high radiation efficiency

in order to overcome the drawback of the low gain of millimeter-wave.

1.4 Scope of the Study

The scope of this project is to gain an experience in designing and simulating

a microstrip grid array antenna in millimetre wave frequencies for 5G mobile

communication network through the literature review and the proposed microstrip

grid array antenna must offer high gain and high radiation efficiency, the simulation

of the proposed microstrip grid array antenna will be conducted to get the simulated

results of the return Loss, Radiation Pattern and the Gain of the antenna by using

CST Microwave Studio software. Finally the optimized microstrip grid array antenna

will be fabricated and measured to compare the measured result with the simulated

result.

1.5 Thesis Outlines

This project report is divided into five chapters, each chapter will explain the

stages of the project design, and these four chapters constituent the project report

was formatted as follows:

Chapter 1 introduces an introduction of why we need to move looking for a

new frequency spectrum specifically millimeter wave frequency spectrum for 5G

mobile communication networks, furthermore this chapter incorporates some view

about the problem statements, objective, and scope of this research project.

Chapter 2 describes the propagation of the millimeter wave at 28GHz and

38GHz and summarizes the work that has been done to investigate the propagation

of the millimeter wave in various environments, and what is the key change that is

required for antenna design to be operating at the new millimeter wave frequency

spectrum, followed by the evolution and the enhancements of the grid array antenna

since it was proposed by John D. Kraus in 1964 up to Zhang & Sun, who received

4

the microstrip grid array antenna on millimeter wave application and the proposed to

use it for antenna in package application (AiP). Also the principle of operation of

microstrip grid-array antennas at millimeter-wave frequencies will be explained in

this chapter including the design parameters (Gain, impedance bandwidth, gain

bandwidth, Half-Power Beam-width and microstrip grid array resonant frequency for

the microstrip grid array antenna. Toward the end of this chapter the Microstrip grid

array antenna Synthesis was introduced flowed by two types of microstrip grid array

antennas (Wideband and Compact, Capacitive Slot feeding).

Chapter 3 the methodology which has been used for the entire project will be

discussed and presented in this chapter in addition, the steps for the proposed

microstrip grid array antenna fabrication process and measurement procedures will

be demonstrated.

Chapter 4 depicts simulated and measurement results. Discussions about

comparisons between simulated and measured result through the diagram are

illustrated.

Chapter 5 concludes this project and indicates some future works.

66

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