cognitive network selection mechanism for multiple

COGNITIVE NETWORK SELECTION MECHANISM

FOR MULTIPLE WIRELESS BROADBAND

TECHNOLOGIES

BY

SUMAYYAH BINTI DZULKIFLY

A dissertation submitted in fulfilment of the requirement for

the degree of Master of Science in Communication

Engineering

Kulliyyah of Engineering

International Islamic University Malaysia

SEPTEMBER 2013

ii

ABSTRACT

The advancement in communication technology has allowed many wireless

broadband services to be introduced into the market. Among them are enhanced data

rates for GSM evolution (EDGE), high speed packet access (HSPA), global packet

radio system (GPRS), universal mobile telecommunications system (UMTS), wireless

fidelity (WiFi), worldwide interoperability for microwave access (WiMAX) and the

newest is long term evolution (LTE) services. A good connectivity is expected to be

realized for users within the multitude of wireless broadband networks. However,

there is disagreement among service providers to merge various broadband

connections into a system. Therefore, there should be an embedded mechanism

capable of intelligently select the best networks without adding the complexity at

user‟s terminal. This concept can be a trade-off to achieve best connectivity. The main

motivation of this research is to develop the solution that has the capability to

optimize the decision making of the best network. This research establishes four

selection algorithms to be embedded in the access point mechanism while considering

the mobile broadband technologies such as HSPA, WiMAX and WiFi. These four

algorithms were formulated according to the principle of heuristic selection algorithm.

Speed variation can be observed through the average connection speed gathered for

one month using non-mobile terminal. This proves the initial assumption of this

research that data connection varies even when the user/terminal is stationary. Thus,

connection speed was established as the indicator for good connectivity. The research

findings had shown that the first and third algorithm have shown the capability to

achieve good connectivity. The fourth algorithm has shown better connection delay as

compared to the other algorithms. In a nutshell, this research had proven that cognitive

network selection mechanism deploying the concept of cognitive radio (CR) and

artificial intelligence (AI) embedded in actual user platform can be realized.

iii

خلاصة البحثABSTRACT IN ARABIC

النطاق ذات اللاسلكية الخدمات من عديد قد عرف الاتصالات تكنولوجيا إن التقدم حزم وصول سرعة وارتفاع ، GSM (EDGE)لتطور الدعززة ومنها البيانات. السوق في العريض

(HSPA)، الراديو لحزمة العالدي والنظام GPRS))، الدتنقلة تللاتصالا العالدي والنظام

(UMTS)، الإخلاص لاسلكي (WiFi) من العالم أنحاء جميع في الدتداخل التشغيل إمكانية (LTE) ىو الطويل الددى على تطور وأحدث ( WiMAX) الدقيقة بالدوجات الوصول أجل

من عدديداً للمستخدمين تتحقق تستطيع أن الجيد الاتصال أن الدفروض ومن. خدمات قادرة آلية ىناك يكون أن يجب الشرط ىذا من بدلا. اللاسلكية يضالعر النطاق شبكات

الدافع. الطرفية المحطة تعقيد إضافة دون الشبكات أفضل بذكاء يتجزأ لا جزءا تحديد على من الدثلى الاستفادة الضعيفة لتحقيق القدرة لديو الذي الحل تطوير ىو البحث لذذا الرئيسي

لا جزءا تكون خوارزميات أربعة باختيار البحث قام ىذا. الشبكات أفضل إلى القرار صنع مثل العريض النطاق ذات الدتنقلة التقنيات ومع ذلك مراعاة على نقطة آلية وصول في يتجزأ

HSPA و WiMAXو .WiFiالأساسي الدبدأ إلى مستداً الأربعة الخوارزميات أشكلت ىذه ملاحظة إن. الدستخدم متطلبات على داالأمور اعتما اختيار لرريات عن الكشف للخوارزميةمهما كانت منصة تجمع أن من الدقدمة الاتصال سرعة خلال من السرعة تنُظر اختلاف

البيانات اتصال أن البحث لذذا الأولية افتراض انطلاقاً من ذلك، قد ثبت. ثابتة تجريبية سرعة أنشئ الذي الدكان ىو ىذا. الأساسية المحطة تحتل الدستخدمين عدد على اعتمادا

آلية تحقيق يمكن أنو أثبتت البحث ىذا من الأخيرة والدرحلة. جيدة اتصال ومؤشر الاتصال تنفيذ واستخدام. الفعلي الدستخدم التشغيل نظام من يتجزأ لا جزءا الدعرفية الشبكة اختيار قد جهزت اتصال جيدة النظام في خوارزمية واختيار الذكاء (AI) الاصطناعي العنصر

مثل جيدة اتصال وصول لتنفيذ الجهاز في الدقترحة اختيار وقد أستخدم مفهوم. للمستخدم الجيش وضباط الأطباء قبل من نشرىا يتم أن وىذا البحث يمكن. الذكية وصول نقطة

اتصال لشبكة الدستمر الوصول إلى يحتاجون الذين البيانات قواعد مديرو ولا سيما والشرطة، جيدة.

iv

APPROVAL PAGE

I certify that I have supervised and read this study and that in my opinion it conforms

to acceptable standards of scholarly presentation and is fully adequate, in scope and

quality, as a thesis for the degree of Master of Science Communications Engineering.

………………………………….

Ahmad Fadzil bin Ismail

Supervisor

…..………………………………

Wahidah Hashim

Co-Supervisor

I certify that I have read this study and that in my opinion it conforms to acceptable

standards of scholarly presentation and is fully adequate, in scope and quality, as a

thesis for the degree of Master of Science Communications Engineering

…..…………………………….

Khaizuran bin Abdullah

Internal Examiner

…..…………………………….

Sharifah Kamilah Syed Yusof

External Examiner

This dissertation was submitted to the Department of Electrical and Computer

Engineering and is accepted as a fulfilment of the requirement for the degree of

Master of Science Communications Engineering.

…..………………………………

Othman O. Khalifa

Head, Department of ECE

This dissertation was submitted to the Kulliyyah of Engineering and is accepted as a

fulfilment of the requirement for the degree of Master of Science Communications

Engineering.

…..………………………………

Md Noor Hj Salleh

Dean, Kulliyyah of Engineering

v

DECLARATION

I hereby declare that this dissertation is the result of my own investigations, except

where otherwise stated. I also declare that it has not been previously or concurrently

submitted as a whole for any other degrees at IIUM or other institutions.

Sumayyah Binti Dzulkifly

Signature………………………..…… Date……………………………..

vi

COPYRIGHT PAGE

INTERNATIONAL ISLAMIC UNIVERSITY MALAYSIA

DECLARATION OF COPYRIGHT AND

AFFIRMATION OF FAIR USE OF UNPUBLISHED

RESEARCH

Copyright © 2013 by International Islamic University Malaysia.

All rights reserved.

COGNITIVE NETWORK SELECTION MECHANISM FOR MULTIPLE

WIRELESS BROADBAND TECHNOLOGIES

No part of this unpublished research may be reproduced, stored in a retrieval

system, or transmitted, in any form or by any means, electronic, mechanical,

photocopying, recording or otherwise without prior written permission of the

copyright holder except as provided below.

1. Any material contained in or derived from this unpublished research may

only be used by others in their writing with due acknowledgement.

2. IIUM or its library will have the right to make and transmit copies (print or

electronic) for institutional and academic purposes.

3. The IIUM library will have the right to make, store in a retrieval system and

supply copies of this unpublished research if requested by other universities

and research libraries.

Affirmed by Sumayyah Binti Dzulkifly

Signature Date

vii

DEDICATION

To my beloved mother and late father, for their eternal love and encouragement.

May Allah S.W.T. always shower them with His Love and Mercy.

viii

ACKNOWLEDGEMENTS

My first and foremost gratitude is to the almighty Allah SWT for granting me His

uncountable blessings throughout my life and making this research work possible. I

would like to express my deepest gratitude to my supervisor, Assoc. Prof. Ir. Dr.

Ahmad Fadzil Ismail, for his numerous advices, academic guidance and support

throughout my research period. Also, I would like to direct special thanks to Dr

Wahidah Hashim from MIMOS Berhad for her unwavering faith of my ability to

finish this research. This dissertation could not be completed without their attentive

supervision, insightful instructions, constructive comments and time given to finish

my research.

I would like to express my gratitude to Dr Mazlan Abbas, Dr Hafizal, Ir. Dr Nordin,

Dr Kwong Kae Hsiang and his research assistants from MIMOS Berhad for their

useful advices and assistance throughout the research.

I am grateful to my mother, Nor A‟ini Binti Rajab for her endless patience, love and

her belief of my potential ability to pursue my Master degree. Not to forget other

family members including my three cherished sisters. Finally, I would like to extend

my thanks to those who had directly and indirectly assisted me in completing my

research.

ix

TABLE OF CONTENTS

Abstract .......................................................................................................................... ii

Abstract in Arabic ......................................................................................................... iii Approval Page ............................................................................................................... iv Declaration ..................................................................................................................... v Copyright Page .............................................................................................................. vi Dedication .................................................................................................................... vii

Acknowledgements ..................................................................................................... viii

List of Tables ............................................................................................................... xii

List of Figures ............................................................................................................. xiii List of Symbols ........................................................................................................... xvi List of Abbreviations ................................................................................................. xvii

CHAPTER ONE: INTRODUCTION ........................................................................ 1 1.1 Introduction ................................................................................................. 1

1.2 Overview ..................................................................................................... 3 1.3 Problem statement ....................................................................................... 6

1.4 Objectives .................................................................................................... 7 1.5 Hypothesis ................................................................................................... 8

1.6 Research Significance ................................................................................. 8 1.6.1 Present Wireless Broadband Scenarios in Malaysia ...................... 10

1.6.1.1 Operator Dependent ......................................................... 10 1.6.1.2 Subscribed Service Dependent ......................................... 11 1.6.1.3 Cell Coverage Dependent ................................................ 12

1.6.1.4 Modem Capacity .............................................................. 13 1.7 Research Scope ......................................................................................... 14

1.8 Brief Research Methodology .................................................................... 15 1.9 Dissertation Outline .................................................................................. 18 1.10 Summary ................................................................................................... 18

CHAPTER TWO: LITERATURE REVIEW ......................................................... 19 2.1 Introduction ............................................................................................... 19

2.2 Wireless Technology Evolution ................................................................ 19 2.3 Cellular Technology Evolution ................................................................. 27 2.4 Industrial, Scientific and Medical (ISM) Radio Band .............................. 30 2.5 Heuristic Selection Algorithm................................................................... 31 2.6 Cognitive Selection Mechanism ............................................................... 34

2.7 Connectivity Performance Indicator ......................................................... 35 2.8 Devices in the Market ............................................................................... 37

2.8.1 WiFiRanger .................................................................................... 37 2.8.2 NICT Mobile Wireless Router Prototype with Cognitive

Capability .....………………………………………………….38 2.8.3 Overall Comparison between the Two Devices ............................ 40

x

2.9 Summary ................................................................................................... 41

CHAPTER THREE: METHODOLOGY ................................................................ 42 3.1 Introduction ............................................................................................... 42 3.2 Hardware Acquisition ............................................................................... 42 3.3 Selection Mechanism Setup ...................................................................... 46 3.4 Selection Programming ............................................................................. 48 3.5 Connection Speed...................................................................................... 50

3.6 Heuristic Model ......................................................................................... 51 3.6.1 Successive Selection (Algorithm 1) ............................................... 52 3.6.2 Comparative Selection (Algorithm 2) ........................................... 53 3.6.3 Evaluative Selection (Algorithm 3) ............................................... 56

3.6.4 Predictive Selection (Algorithm 4) ................................................ 58 3.7 Summary ................................................................................................... 60

CHAPTER FOUR: FINDINGS AND DISCUSSION ............................................. 61 4.1 Introduction ............................................................................................... 61 4.2 Individual Connection Speed Performance Evaluation ............................ 61

4.2 Heuristic Model Evaluation ...................................................................... 69 4.4 Connection Speed Output at MIMOS Berhad ............................................ 71

4.4.1 Connection Speed Output of Successive Selection

(Algorithm 1) ................................................................................. 71 4.4.2 Connection Speed Output of Comparative Selection

(Algorithm 2) ................................................................................. 73

4.4.3 Connection Speed Output of Evaluative Selection

(Algorithm 3) ................................................................................. 74 4.4.4 Connection Speed Output of Predictive Selection

(Algorithm 4) ................................................................................. 75 4.4.5 Selection Algorithm Performance Analysis .................................. 77

4.5 Connection Speed Output at Bandar Tun Hussein Onn ............................ 82

4.5.1 Connection Speed Output of Successive Selection

(Algorithm 1) ................................................................................. 83

4.5.2 Connection Speed Output of Comparative Selection

(Algorithm 2) ................................................................................. 84 4.5.3 Connection Speed Output of Evaluative Selection

(Algorithm 3) ................................................................................. 86 4.5.4 Connection Speed Output of Predictive Selection

(Algorithm 4) ................................................................................. 87 4.5.5 Selection Algorithm Performance Analysis .................................. 88

4.6 Graphical User Interface (GUI) ................................................................ 92 4.7 Summary ................................................................................................... 93

CHAPTER FIVE: CONCLUSION AND RECOMMENDATIONS .................... 94 5.1 Conclusion ................................................................................................ 94 5.2 Recommendations ..................................................................................... 95 5.3 Summary ................................................................................................... 96

xi

REFERENCES ........................................................................................................... 97

LISTS OF INTELLECTUAL PROPERTY PATENT ......................................... 102 LISTS OF PUBLICATIONS .................................................................................. 103 LISTS OF AWARDED CONFERENCE PAPER ................................................ 104

APPENDIX A: SELECTION ALGORITHMS ......................................................... 105

APPENDIX B: SELECTION OUTPUT SAMPLE FROM TERMINAL

(ALGORITHM 1) ...................................................................................................... 112 APPENDIX C: SELECTION OUTPUT SAMPLE FROM TERMINAL

(ALGORITHM 2) ..................................................................................................... 113

APPENDIX D: SELECTION OUTPUT SAMPLE FROM TERMINAL

(ALGORITHM 3) ...................................................................................................... 115 APPENDIX E: SELECTION OUTPUT SAMPLE FROM TERMINAL

(ALGORITHM 4) ...................................................................................................... 116 APPENDIX F: GUI SCREENSHOTS ...................................................................... 117

xii

LIST OF TABLES

Table No. Page No.

1.1 Example of the subscription package 12

2.1 Summary of wireless technology evolution from 1838 to

1950s

20

2.2 Summary of wireless technology evolution from 1960s to

1985

22

2.3 Summary of wireless technology evolution from 1990 to

2000

24

2.4 Summary of wireless technology evolution from 2003

onwards

26

2.5 Overall cellular systems 28

2.6 ISM radio bands review 30

2.7 Overall comparisons of the devices 39

3.1 Summary of the pros and cons of hardware for the selection

platform purpose

44

4.1 Investigation attributes 62

4.2 Service details 62

4.3 Overall connectivity durations summary 80

4.4 Overall connectivity durations summary 91

xiii

LIST OF FIGURES

Figure No. Page No.

1.1 User device connected to multiple broadband modems 3

1.2 Optimized network connection mechanism 6

1.3 Policeman using portable device to access database 10

1.4 Examples of coverage area offered by a broadband operator 13

1.5 Research methodology 17

2.1 Basic performance optimization model (Rice, J. R., 1975) 32

2.2 Fundamental array pseudo-code (Millington, I., & Funge,

J., 2009)

33

3.1 Arduino Duemilanove 42

3.2(a) Freescale‟s MPCDB 43

3.2(b) Compex PCBA-WP 188 DB 43

3.3 Network diagram of selection mechanism from access

point perspective

46

3.4 Real selection mechanism from access point perspective 47

3.5 Cognitive selection stages 48

3.6 GUI screen capture of the download and upload connection

speed

50

3.7 Successive selection 52

3.8 Comparative selection 54

3.9 Evaluative selection 56

3.10 Predictive selection 58

4.1 Lab setup 61

4.2 Investigation location in MIMOS Berhad building 61

xiv

4.3 Average connection speed gathered from 10:00 to 23:00 the

next day)

63

4.4 Averaged broadband connection speed from 10:00 until

14:00

64

4.5 Disclaimer notice from mobile broadband 1 service

provider‟s website

64


18:00

65


22:00

65


02:30

66


06:40

67


10:50

67

4.11 Investigation setup (MIMOS Berhad) 70

4.12 Global positioning system (GPS) coordinate of the

experimental avenue

71

4.13 Successive selection output (MIMOS Berhad) 72

4.14 Comparative selection output (MIMOS Berhad) 74

4.15 Evaluative selection output (MIMOS Berhad) 75

4.16 Predictive selection output (MIMOS Berhad) 76

4.17 Profiled database for predictive selection (average

connection)

77

4.18 Optimized speed performance analysis of each algorithm 78

4.19 Delay analysis for each algorithm 79

4.20 Standard deviation in time of the day 80

4.21 Investigation setup (Bandar Tun Hussein Onn) 82

xv

4.22 Global positioning system (GPS) coordinate of the

experimental avenue (Bandar Tun Hussein Onn)

83

4.23 Successive selection output (Bandar Tun Hussein Onn) 84

4.24 Comparative selection output (Bandar Tun Hussein Onn) 85

4.25 Evaluative selection output (Bandar Tun Hussein Onn) 86

4.26 Predictive selection output (Bandar Tun Hussein Onn) 87

4.27 Profiled database for predictive selection (average

connection)

88

4.28 Optimized speed performance analysis of each algorithm 89

4.29 Delay analysis for each algorithm 90

4.30 Standard deviation in time of the day 91

4.31 GUI sample displaying the connection condition 87

xvi

LIST OF SYMBOLS

© Copyright sign

≈ Almost equal to

= Equal to

Σ Summation

σ Standard deviation

≥ Greater than or equal to

≤ Less than or equal to

xvii

LIST OF ABBREVIATIONS

1G First Generation

2G Second Generation

3G Third Generation Mobile System

4G Fourth Generation Mobile System

AI Artificial Intelligence

AMPS Advanced Mobile Phone Service

CA Cognitive Algorithm

CR Cognitive Radio

CSM Cognitive Selection Mechanism

DQPSK Differential Quaternary Phase-Shift Keying

EDGE Enhanced Data Rates for Global Evolution

ETACS European Total Access Communication System

FCC Federal Communication Commission

FDMA Frequency Division Multiple Access

FL Fuzzy Logic

GMSK Gaussian Minimum Shift Keying

GPRS General Packet Radio Service

GSM Global System for Mobile Communication

HAS Heuristic Selection Algorithm

HSPA High Speed Packet Access

HWN Heterogenous Wireless Network

IMTS Improved Mobile Telephone Service

NTT Nippon Telephone and Telegraph

QPSK Quadrature Phase Shift Keying

RCC Radio Common Carriers

TDMA Time Division Multiple Access

UMTS Universal Mobile Telecommunications System

WCDMA Wideband Code Division Multiple Access

WIMAX Wireless interoperability for Microwave Access

WIFI Wireless Fidelity

1

CHAPTER ONE

INTRODUCTION

1.1 INTRODUCTION

The existence of heterogeneous wireless networks (HWN) should evidently lead to

ubiquitous communication environment that allow user/s to connect seamlessly

among the different networks. However, to achieve such feat or capability, it does

involve a complex system configuration. This is indeed a challenging task for the

network provider, operator as well as communication devices in order to support such

scenario for better Quality of Service (K.J. Ray Liu, 2011). Recent advancement in

Cognitive Radio (CR) technology might be exploited as one of the means capable of

perfecting connectivity among multiple users. This can be realized by sensing the

existing networks characteristics (Haykin, S., 2005).

Cognitive adaptation algorithm is a component in CR technology where

intelligence and acumen are devised. Based on specific tasks, it can be part of the

advanced mechanism capable to choose the most optimum network characteristics.

Such concept can also be applied in network selection mechanism to achieve better

connectivity performance. The aim for smart network selection mechanism is to

provide the communication device with proactive decision in contrast to passive

decision while maintaining minimal complexity of the system.

Among available algorithms that had been proposed for theoretical

implementation of network selection mechanism are likely based on fuzzy logic (FL),

genetic algorithms, game theory and particles swarm optimization (Alkhawlani, M.,

&Ayesh, A., 2008). These have been extensively used in maximizing the handover

2

decision in wireless mobile nodes with the justification that they increase the handover

efficiency within the protocol (Raoof, O., & Al-Raweshidy, H., 2009). However,

practical embedment require less complex algorithms to reduce machine complexity

namely heuristic algorithms (Liu, Z., Nasser, N., & Hassanein, H. S., 2013; Wang, S.,

Huang, F., & Zhou, Z. H., 2011).

The currently available wireless broadband technologies include global packet

radio system (GPRS), universal mobile telecommunications system (UMTS), fourth

generation wireless system (4G), wireless fidelity (WiFi) as well as worldwide

interoperability for microwave access (WiMAX) services. Literatures do highlight that

research in network selection mechanism is of high interest. Fathy, R. A. et al., (2013)

presented the adaptation of meta-heuristic engine in cognitive radio system using

MATLAB programming. Nonetheless, approach or approaches that incorporate

cognitive element within the selection mechanism can be considered non-existence or

very limited (Haykin, S., 2005).

Citing an example, a specific user might have multiple wireless broadband

services available at one's disposal as illustrated in Figure 1.1. These somehow still

need to be manually activated and the user will have to configure by him or herself the

best network connection to use. The selection process may be based on availability of

service, service signal strength and data rate parameters. Obviously, such manual

network selection activities can prove to be inefficient, time consuming and

cumbersome.

3

Figure 1.1: User device connected to multiple broadband modems

The preliminary goal of this study is to develop and formulate novel

algorithms for selecting best network connectivity based on the principle of cognitive

radio which has not yet been ventured into by any other techniques. The selection

algorithms developed are tested in real wireless environment to observe their

efficiency in providing best connectivity. The findings of this research will be

elaborated in the discussion and conclusion chapter.

1.2 OVERVIEW

Wireless communication is the method of relaying a message without using any

visible physical medium from one point to another. The earliest possible mode of long

distance wireless communication might have started off with the usage of smokes at

the top of the mountain (Andrea, G., 2005). Realizing that it is vital for the receiver to

receive a correct message without the fuss of using the wires especially during the war

4

time, the first telegraph machine was introduced by Samuel Morse in 1838 (Andrea,

G., 2005). The introduction of the first telegraph machine pioneered further evolution

in wireless communication technology as the demand of transmitting more reliable

messages increased. Today, broadband services have been introduced as part of the

recent advancement in the technology with the capability to send and receive more

messages or data.

There are arising issues especially from the user's perspective as these new

wireless technologies are being introduced every year. One of the main issues is the

limited capability of getting good connectivity despite the purchase of the latest

broadband technologies (hardware and services) introduced in the market. Eighty one

percent national broadband penetrations in Malaysia were anticipated by the end of

2011, which likely to cause massive broadband traffic especially within the highly

dense population area such as the city Kuala Lumpur (The Star, 2012 & Bernama

2012). To mitigate the broadband traffic issue, service providers had deployed micro-

cells where smaller cells were introduced in order to cater high connectivity with

bigger capacity of users. This incurred a lot of cost for the service providers thus limit

the installation numbers of micro-cell. Due to this, not all users are guaranteed to have

good connectivity at all-time despite their efforts of buying the most expensive

wireless broadband technologies.

Meanwhile, the less populated areas such as the rural village are facing limited

connectivity problems such as low data rates. This is due to limited capability of the

base station as specified by the service providers. The base stations within the rural

areas are usually equipped with the technology that can provide wider coverage. As a

trade-off for wider coverage, the lower transmission frequency is used thus limiting

the number of data that can be exchanged. From the perspective of the broadband

5

service providers, the trade-off is acceptable since their initial estimation is that there

will be low requirements for broadband traffic within the rural area as compared to

those in the cites.

Apart from that, they also need to consider the profits and loss in deploying

more sophisticated technology within the area with considerably low broadband

usage. Initially, this seems to be a good trade-off for rural area in Malaysia. However,

the village areas tend to be highly congested especially during the festive seasons.

This is when "city people" go back to their hometowns and start utilizing broadband

services all at the same time. Due to this, Malaysian government embarked on

ongoing initiatives such as emphasizing the plan to reach higher broadband

penetration within the rural area (Bernama, 2012). The initiative, however, requires an

extensive planning, huge capital and certainly involves long-term deployment

(Bernama, 2012 & MCMC, 2012).

Malaysian researchers had proposed several methods to resolve the broadband

traffic issues faced by the service providers (MohdHasbullah Omar, 2009). One of

them includes introducing the new cognitive radio technology that manipulates and

exploits the unused wireless spectrum in Malaysia (MohdHasbullah Omar, 2009). The

effort of implementing the technology is still ongoing but it requires a lot of time to be

realized due to the complexity and level of acceptance between the spectrum owners.

This is where the cognitive network selection mechanism can be introduced to provide

more flexible solution without causing concerns to any spectrum owner.

The concept of cognitive wireless network selection mechanism incorporates

the deployment of intelligent algorithm at physical layer of the network. The service

selections for primary user will be made based on the subscribed connection speed.

The selection engages internal analysis that had been structured to monitor the

6

behaviour of the network in terms of connection speed. The research includes

investigation and flexibility analysis of cognitive network selection mechanism

capability in providing good connection without compromising the other broadband

users within the spectrum. Figure 1.2 below portrays the diagram of optimized

network connection mechanism.

Figure 1.2: Optimized network connection mechanism

1.3 PROBLEM STATEMENT

With multiple subscriptions of wireless broadband networks, a good connectivity

should be or expected to be realized for users. Nevertheless, there are still pitfalls in

achieving such plateau due to policy issues among network operators. For example, a

WIMAX operator cannot offer UMTS or GPRS without having the license or network

infrastructure offering these additional services. However, with reduction in the

subscription cost and increase of coverage in the future, it can be foreseen that users

can afford to subscribe multiple networks to ensure access to the best quality of

7

services (QoS). In lieu of such requirement, there should be a device embedded with

network selection mechanism intelligent enough to support this capability without

increasing the communication terminal complexity.

In order to implement the intelligence element into the system, a device with a

specified algorithm and software assistant (SA) should be deployed into multiple

wireless broadband system. It should be capable of acquiring and processing real time

data available such as received signal strength (RSS), data rate, service type, packet

transfer rate, BER, and others. This research will investigate and identify the most

suited algorithms.

Based on the review carried out, the most suitable selection algorithm capable

of providing best connectivity while minimizing its complexity to the system had been

identified as heuristic selection algorithm. The formulated algorithm will be

embedded into a specific wireless system to be deployed for real time testing. The

outcome of the selection algorithm will be presented in the discussion and conclusion

chapter.

1.4 OBJECTIVES

The main motivation of this research is to create a program that would enable network

selection with cognitive capability by employing algorithms to work in a system that

considers HWN. In order to achieve the mentioned goal, this research should follow

the following objectives:

To identify relevant selection algorithm from the background studies.

To investigate how cognitive sciences are incorporated in smart network

selection mechanism.

To develop and formulate specific network selection mechanism.

cognitive network selection mechanism for multiple

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