UNIVERSITI PUTRA MALAYSIA

WASAN AHMAD SULIEMAN ALFRAIHAT

FK 2010 48

MULTI-CHANNEL SUPPORT FOR DATA-GATHERING TREES IN WIRELESS SENSOR NETWORKS

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MULTI-CHANNEL SUPPORT FOR DATA-GATHERING TREES IN

WIRELESS SENSOR NETWORKS

BY

WASAN AHMAD SULIEMAN ALFRAIHAT

Thesis Submitted to the School of Graduate Studies, University Putra

Malaysia, in Fulfilment of the Requirements for the Degree of Master of

Science

September 2010

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Abstract of thesis presented to the Senate of University Putra Malaysia in

fulfilment of the requirement for the degree of Master of Science

MULTI-CHANNEL SUPPORT FOR DATA GAHTERING-TREES IN

WIRELESS SENSOR NETWORKS

By

WASAN AHMAD SULIEMAN ALFRAIHAT

September 2010

Chairman: Mohd. Fadlee A. Rasid, PhD

Faculty: Engineering

In traditional applications of Wireless Sensor Networks (WSNs), energy

efficiency may be considered to be the most important concern whereas utilizing

the bandwidth and maximizing the throughput are of secondary importance.

However, recent applications, such as structural health monitoring, require high

amounts of data to be collected at a faster rate. Furthermore, it is possible to have

multiple applications running on the same network, especially with some

operating systems for WSNs. This certainly leads to larger amounts of data to be

transmitted in the network and handling the traffic. In general, multi-channel

scheme is widely used in wireless networks, to reduce the interference and to

increase the throughput. Although that current radios support up to 16 channels,

this is not enough to allow all of the nodes which are in the same interference

range to transmit concurrently especially in dense networks. A new multi-channel

duty cycle protocol, known as Adaptive Fast Convergecast MAC (AFC-MAC), is

proposed especially for data gathering tree which combines the staggered wake up

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schedule with the multi-channel approach to reduce the number of competing

nodes in order to get a transmission. AFC-MAC composed of two phases, the

channel assignment phase and the adaptive scheduling phase. The channels are

assigned to the nodes in a way to allow the nodes to send the data packets with a

minimum delay by eliminating the interference with the concurrent transmissions

of the next nodes along the path, and at the same time the nodes consider the

impact of the adjacent channels in the channel assignment decision. This

interference elimination helps the nodes to schedule the next active time-slots

time cycle with a minimum delay to adapt to the network’s high traffic rate. The

two-way data forwarding is supported by the adaptive schedule phase by adopting

a special synchronization mechanism to avoid the contradiction with the sink’s

reports forwarding. One of the multi-channel duty cycle protocols, Path-Oriented

Real Time MAC protocol (PR-MAC) is examined and simulated using the ns2

simulation environment. AFC-MAC is compared with PR-MAC in terms of

Aggregate MAC throughput, delivery ratio, and energy efficiency. Since AFC-

MAC assigns the channels to nodes rather than paths, the convergecast speed and

the throughput has been enhanced. Specifically, the throughput is enhanced 4.784

times to the achieved throughput in PR-MAC, and the delivery ratio in AFC-

MAC has been enhanced 2.242 times compared to PR-MAC.

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Abstrak tesis yang dikemukakan kepada Senat Universiti Putra Malaysia Sebagi

memenuhi keperluan untuk ijazah Master Sains

SOKONGAN PELBAGAI SALURAN UNTUK PENGUMPULAN

PEPOHON DATA DALAM RANGKAIAN PENDERIA TANPA WAYAR

Oleh

WASAN AHMAD SULIEMAN ALFRAIHAT

September 2010

Pengerusi: Mohd. Fadlee A. Rasid, PhD

Fakulti: Kejuruteran

Dalam applikasi tradisional Rangkaian Penderia Tanpa Wayar (WSN), kecekapan

tenaga boleh dianggap sebagai ciri terpenting di mana kadar penggunaan jalur

saluran dan pemaksimuman kadar pemprosesan diletakkan di takuk kedua.

Walaubagaimanapun, dalam applikasi terkini, contohnya seperti pemantauan

tunjang kesihatan, memerlukan pengumpulan amaun data yang banyak pada kadar

yang lebih laju. Tambahan pula, adalah mungkin pelbagai applikasi berjalan

serentak dalam rangkaian yang sama, terutamanya dengan beberapa sistem

operasi tertentu untuk WSN. Ini sudah tentunya membawa kepada pemancaran

amaun data yang lebih tinggi melalui rangkaian dan pengelolaan trafik. Secara

umumnya, skim pelbagai saluran digunakan secara meluas dalam rangkaian

penderia tanpa wayar, untuk mengurangkan interferens dan meningkatkan kadar

pemprosesan. Walaupun radio masa kini mampu menyokong sehingga 16 saluran,

namun ini masih tidak mencukupi untuk membenarkan semua nod yang berada

dalam julat interferens memancar secara serentak terutamanya dalam rangkaian-

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rangkaian yang padat. Satu protokol duty cycle pelbagai saluran yang bijak,

Adaptive Fast Convergecast MAC (AFC-MAC), dicadangkan terutamanya untuk

pengumpulan pepohon data yang menggabungkan jadual bangun berperingkat

dengan menggunakan pendekatan pelbagai saluran untuk mengurangkan jumlah

nod yang berlumba-lumba untuk mendapatkan transmisi. AFC-MAC terdiri

daripada dua fasa, iaitu fasa peruntukan saluran dan fasa penyesuaian

penjadualan. Saluran-saluran ini diperuntukkan kepada nod-nod dalam cara yang

membenarkan nod-nod tersebut menghantar peket data dengan kadar pelambatan

minimum dengan menghapuskan interferens melalui transmisi serentak nod-nod

berikutnya sepanjang laluan itu, dan pada masa yang sama nod-nod tersebut

mengambilkira impak terhadap saluran-saluran bersebelahan semasa keputusan

peruntukan saluran dibuat. Penghapusan interferens ini menolong nod-nod

tersebut untuk menjadualkan kitar masa slot-masa aktif yang berikutnya dengan

kadar pelambatan minimum untuk menyesuaikan diri kepada kadar trafik

rangkaian yang tinggi. Penyampaian data dua-hala disokong oleh fasa

penyesuaian penjadualan dengan menggunakan mekanisma sinkronisasi khas

untuk mengelakkan kontradiksi dengan laporan sinki penyampaian. Salah satu

daripada protokol duty cycle pelbagai saluran, protokol Path-Oriented Real Time

MAC (PR-MAC) dikaji dan disimulasi menggunakan persekitaran simulasi ns2.

AFC-MAC dibandingkan dengan PR-MAC dari segi kadar pemprosesan Agregat

MAC, nisbah penghantaran, dan kecekapan tenaga. Memandangkan AFC-MAC

memperuntukkan saluran kepada nod dan bukannya laluan, kelajuan convergecast

dan kadar pemprosesan telah berjaya dipertingkatkan. Secara terperinci, kadar

pemprosesan dipertingkatkan 4.784 kali ganda berbanding dengan kadar

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pemprosesan tercapai oleh PR-MAC, dan nisbah penghantaran dalam AFC-MAC

telah berjaya dipertingkatkan 2.242 kali ganda berbanding dengan PR-MAC.

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ACKNOWLEDGEMENTS

I would like to express my sincere gratitude to my supervisor Dr. Mohd. Fadlee

A. Rasid for his realistic, encouraging, and constructive approach throughout my

masters study and his efforts during supervision of my thesis.

I would like to express my appreciation to my colleagues for understanding and

support during my academic studies.

Finally, I would like to express my thanks to my parents for their love, trust,

understanding, and every kind of support not only throughout my thesis but also

throughout my life.

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I certify that a Thesis Examination Committee has met on (29/9/2010

) to conduct the final examination of Wasan Ahmad Sulieman Alfraihat on his

thesis entitled “Multi-Channel Support For Data Gathering Trees in Wireless

Sensor Networks” in accordance with the Universities and University Colleges

Act 1971 and the constitution of the University Putra Malaysia [P.U.(A) 106] 15

March 1998. The Committee recommends that the student be awarded the Master

of Science in Wireless Communication Engineering.

Members of the Thesis Examination Committee were as follows:

Ahmad Fauzi Abas, PhD

Dr. Ing

Department of Computer and Communications Engineering

Faculty of Engineering

University Putra Malaysia

(Chairman)

Nor Kamariah Noordin, PhD

Associate Professor

Department of Computer and Communications Engineering

Faculty of Engineering

University Putra Malaysia

(Internal Examiner 1)

Alyani Ismail, PhD

Assistant Professor

Department of Computer and Communications Engineering

Faculty of Engineering

University Putra Malaysia

(Internal Examiner 2)

Farhat Anwar, PhD

Professor

Department of Electrical and Computer Engineering

Faculty of Engineering

International Islamic University Malaysia

Malaysia

(External Examiner)

BUJANG KIM HUAT, PhD

Professor and Deputy Dean

School of Graduate Studies

University Putra Malaysia

Date:

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This thesis was submitted to the Senate of University Putra Malaysia and has been

accepted as fulfilment of the requirement for the degree of Master of Science. The

members of the Supervisory Committee were as follows:

Mohd. Fadlee A. Rasid, PhD

Assistant Professor

Faculty of Engineering

University Putra Malaysia

(Chairman)

Aduwati Sali, PhD

Assistant Professor

Faculty of Engineering

University Putra Malaysia

(Member)

HASANAH MOHD GHAZALI, PhD

Professor and Dean

School of Graduate Studies

University Putra Malaysia

Date:

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DECLARATION

I declare that this thesis is my original work except for quotations and citations

which have been duly acknowledged. I also declare that it has not been

previously, and is not concurrently, submitted for any other degree at University

Putra Malaysia or at any other institution.

WASAN AHMAD SULIEMAN ALFRAIHAT

Date: 29/9/2010

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TABLE OF CONTENTS

Page

ABSTRACT ii

ABSTRAK iv

ACKNOWLEDGEMENTS vii

APPROVAL viii

DECLARATION x

LIST OF TABLES xiii

LIST OF FIGURES xiv

LIST OF ABBREVIATIONS xvi

CHAPTER

1 INTRODUCTION 1

1.1 Wireless Sensor Networks 2

1.2 Communication between Wireless Sensor Devices 4

1.3 Problem Statement 7

1.4 Aims and Objectives 8

1.5 Contribution 9

1.6 Thesis Outline 11

2 LITERATURE REVIEW 12

2.1 Capacity Limitations in Wireless Sensor Networks 13

2.1.1 Interference 15

2.1.2 Radio Limited Capabilities 18

2.2 Single-Channel MAC Protocols in WSNs 21

2.3 Multi-Channel MAC Protocols in Ad Hoc Networks 23

2.3.1 Single-Radio Multi-Channel Wireless Ad-Hoc

Neworks 25

2.3.2 Multi-Radio Multi-Channel Wireless Ad-Hoc

Networks 30

2.3.3 Comparisons 32

2.4 Multi-Channel Protocols in WSNs 35

2.4.1 Existing Work 36

2.4.2 Comparisons 44

3 METHODOLOGY 47

3.1 Assumptions 47

3.2 Description of the algorithm 48

3.2.1 The Channel Assignment Phase 52

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3.2.2 Adaptive Scheduling Phase 62

3.3 Summary 67

4 RESULTS AND ANALYSIS 69

4.1 Simulation Background 71

4.2 Benchmark Verification 72

4.3 Performance Evaluation 74

4.3.1 Scenario One: Multi-Hop Chain Test 75

4.3.2 Scenario Two: Energy versus Time 77

4.3.3 Scenario Three: Network with Three Uncrossed

Forwarding Paths 83

4.3.4 Scenario Four: Performance Evaluation with

Different System Loads 88

4.4 Summary 91

5 SUMMARY, CONCLUSIONS AND

RECOMMENDATIONS FOR FUTURE WORK 93

5.1 Conclusion 93

5.2 Future Work 96

REFERENCES 98

APPENDICES 108

BIODATA OF STUDENT 126