DEVELOPMENT OF COOPERATIVE RELAY USING UNIVERSAL

SOFTWARE RADIO PERIPHERAL

MUHAMMAD RUSHIDI SABIRIN

A project master submitted in fulfilment of the

requirements for the award of Master of

Engineering (Electrical-Electronics & Telecommunications)

Faculty of Electrical Engineering

Universiti Teknologi Malaysia

JANUARY, 2015

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Specially dedicated to my mother Siti Aishah Omar and my father Sabirin Ikhsan also

my brothers Mohammad Rashid, Mohammad Ridhuan and Mohammad Radzi who

have encourage, guide and inspired me throughout my entire life.

Hopefully, all the contributions are blessed by Allah S.W.T, The Mighty Creator.

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ACKNOWLEDGMENT

Alhamdulillah, I’m really grateful to Allah S.W.T with his greatness and

blessing for giving me the strength in accomplishing this project in needed period.

I would like to extend my sincerest gratitude to my supervisor, Dr Bruce

Leow Chee Yen for his assistance, guidance and patience throughout the work of

completing this project report and the final year project. The suggestion and

recommendation from him is so helpful to finish the project.

Dedications to all my family members especially my beloved mother and

father and also my brothers who were always be there with support, courage and help

whenever I need them at most, I really always be thankful to them.

Then, the last but not least are for my friends Kak Mardiah morsin and

Nurfateha Othman who are helped me breakthrough this entire studies with rise and

falls together, I do still appreciate your contribution and help.

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ABSTRACT

To meet the demand for high speed data, wireless cellular system technology

has grown in a steady pace. However, the wireless signals are still vulnerable to the

multipath fading, shadowing and path loss, making the communication less reliable.

Cooperative relay is a techniques to improve signal reliability by introducing a an

additional node between source terminal and destination terminal to provide

redundant path for data transmission. However, existing work of cooperative relay

investigate performance through theoretically simulation only. The real world

performance remains unknown because the lack of prototype for field testing and

measurement. The focus of this work is therefore to implement the cooperative relay

prototype using Universal Software Radio Peripheral (USRP) and LabVIEW

platform. The relay prototype based on Amplify-and-Forward (AF) protocol has been

developed. The performance in terms of bit error rate (BER) of the cooperative relay

link is compared with the direct link without relay. The measurement is carried out in

the indoor environment. Measurement results show that the cooperative relay

significantly improves the signal reliability and extends the coverage distance if

compared to direct communication without relay.

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ABSTRAK

Dalam usaha untuk memenuhi tuntutan untuk data berkelajuan tinggi telah

menyebabkan perkembangan pesat dalam teknologi wayarles sistem selular akan

tetapi isyarat wayarles masih terdedah kepada kesan pelbagai arah yang pudar ,

membayangi dan rendah kekuatan isyarat yang menyebabkan isyarat kurang

diperolehi. Geganti Koperasi adalah teknik yang mampu meningkatkan

kebolehpercayaan isyarat dengan memperkenalkan geganti pautan sebagai nod

tambahan antara terminal sumber dan terminal destinasi. Walau bagaimanapun,

kerja-kerja yang telah dibuat oleh penyelidik ,dengan menyiasat prestasi relay

koperasi melalui teori atau prototaip simulasi akan tetapi bahawa prototaip adalah

penting dimana ia boleh diuji prestasinya sebelum dilaksanakan dalam persekitaran

sebenar.Fokus dalam kerja ini adalah untuk melaksanakan komunikasi koperasi

berdasarkan Universal Perisian Radio Persisian (USRP) dan platform LabVIEW

dalam persekitaran yang sebenar. Teknik relay berdasarkan Amplift-dan-Forward

(AF) diimplikasikan pelaksanaanya. Prestasi perbandingan kadar ralat bit (BER)

antara pautan geganti kerjasama dengan pautan langsung telah dinilai. Persediaan

eksperimen dijalankan dengan senario yang berbeza dan dijalankan dalam kawasan

persekitaran tertutup. Hasil keputusan menunjukkan pautan geganti koperasi dapat

meningkatkan prestasi dari segi kebolehpercayaan isyarat dan liputan jarak lanjutan.

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TABLE OF CONTENTS

CHAPTER TITLE PAGE

DECLARATION ii

DEDICATION iii

ACKNOWLEDGEMENT iv

ABSTRACT v

ABSTRAK vi

TABLE OF CONTENTS vii

LIST OF TABLES x

LIST OF FIGURES xi

LIST OF ABBREVIATIONS xiii

LIST OF SYMBOLS xv

LIST OF APPENDIX xvi

1 INTRODUCTION 1

1.1 Project Background 1

1.2 Problem Statement 2

1.3 Research Objectives 2

1.4 Scope 2

1.5 Thesis outline 3

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2 LITERATURE REVIEW 4

2.1 Introduction 4

2.2 Cooperative Relay 5

2.3 Amplify and Forward 6

2.4 Orthogonal Frequency-Division Multiplexing 7

2.5 Software Defined Radio 7

2.6 Universal Software Radio Peripheral 8

2.7 NI USRP 2922 Hardware 9

2.8 LabVIEW National Instrument Software 11

2.9 Related Work 12

3 METHODOLOGY 14

3.1 Introduction 14

3.2 First Phase of Direct Link Development 16

3.2.1 A Source Terminal 16

3.2.2 Destination Terminal 19

3.3 Second Phase Cooperative Relay Link Development 22

3.3.1 A Relay Terminal 22

3.3.2 Destination Terminal Aided By A Cooperative Relay Link 24

3.4 Performance Measurement 25

3.5 Indoor Measurement Setup 26

3.6 Hardware Configuration 29

4 RESULT AND DISCUSSION 31

4.1 Introduction 31

4.2 Experimental result and analysis 31

4.3 Outdoor propagation measurement 37

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5 CONCLUSION AND FUTURE WORK 39

5.1 Conclusion 39

5.2 Recommendation and future work 39

REFERENCES 40

APPENDIX A 42

x

LIST OF TABLES

TABLE NO. TITLE PAGE

3.1 Hardware’s specification used for this project 29

3.2 Indoor measurement parameter setup 30

xi

LIST OF FIGURES

FIGURE NO. TITLE PAGE

2.1 (a) Direct Link Communication 5

(b) Relay Link Communication 5

2.2 Schematic representation of Amplify and Forward 6

2.3 Each subcarrier orthogonal to each other by overlapping 7

2.4 a) Conventional radio (b) SDR 8

2.5 NI USRP-2920 System Block Diagram 9

2.6 NI-USRP configuration utility for connecting of USRP to the

host computer 10

2.7 NI USRP 2922 device 11

2.8 Transmitter and receiver module using the LabVIEW Modulation

Toolkit 12

3.1 Flowchart of the project 15

3.2 Block diagram of source terminal 16

3.3 VI block diagram OFDM at source terminal 17

3.4 VI block diagram for source terminal 18

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3.5 The front panel of source terminal 18

3.6 Block diagram of destination terminal 19

3.7 VI block diagram OFDM at destination terminal 20

3.8 VI block diagram for destination terminal 21

3.9 The front panel of destination terminal 22

3.10 Block diagram of relay terminal 22

3.11 VI block diagram for relay terminal 23

3.12 The front panel of relay terminal 24

3.13 Block diagram of cooperative relay link at destination terminal 24

3.14 VI block diagram of cooperative relay assisted communication

at destination terminal 25

3.15 VI block diagram of computing BER 26

3.16 (a) The layout of direct link (b) The direct link experiment setup 27

3.17 (a) The layout of cooperative relay link (b) The cooperative relay

link experiment setup 28

4.1 The direct link result at 20 meter from source terminal 32

4.2 The cooperative relay link result at 20 meters from source terminal 32

4.3 Comparison of direct link and cooperative relay link using

inbound frequency at 100 kHz bandwidth 33

4.4 Comparison of direct link and cooperative relay link using

inbound frequency at 200 kHz bandwidth 34

4.5 Cooperative relay link using outbound frequency at 100 kHz

bandwidth 35

4.6 Comparison BER vs SNR for cooperative relay link with

direct link 36

4.7 Verification of data measured with the theoretical calculation 37

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LIST OF ABBREVIATIONS

1G - First Generation

4G - Fourth Generations

MIMO - Multiple Input and Multiple Output

SDR - Software Defined Radio

NI - National Instrument

USRP - Universal Software Radio Peripheral

BER - Bit Error Rate

AF - Amplify & Forward

OFDM - Orthogonal Frequency-Division Multiplexing

SISO - Single Input Single Output

LOS - Line of Sight

N-LOS - Non Line of Sight

eNB - enhanced Node B

UE - User Equipment

DF - Decode & Forward

QAM - Quadrature Amplitude Modulation

PSK - Phase Shift Keying

ADC - Analog to Digital Converter

DAC - Digital to Analog Converter

DSP - Digital Signal Process

FPGA - Field Programmable Device Array

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FM - Frequency Modulation

AM - Amplitude Modulation

PM - Phase Modulation

ASK - Amplitude Shift Keying

FSK - Frequency Shift Keying

PAM - Pulse-Amplitude Modulation

QPSK - Quadrature Phase Shift Keying

GMSK - Gaussian Minimum-Shift Keying

MSK - Minimum-Shift Keying

2D - Two Dimensions

3D - Three Dimensions

WARP - Wireless Open-Access Research Platform

LTE - Long-Term Evolution

PC - Personal Computer

IP - Internet Protocol

FFT - Fast Fourier transforms

VI - Virtual Instrument

SNR - Signal to Noise Ratio

xv

LIST OF SYMBOLS

dB - Decibel

m - meter

Hz - Hertz

xvi

LIST OF APPENDIX

APPENDIX TITLE PAGE

A Datasheet NI USRP 2922 43

1

CHAPTER 1

INTRODUCTION

1.1 Project Background

The growing demand of data applications has led significant development in

wireless communications. The development of cellular networks from first

generation, 1G until the latest fourth generation, 4G is due to the demand in high

speed data rate among the users. However, to provide an improvement of signal

reliability and enhanced system capacity remains a challenge. This is due to various

propagation effects like path loss, shadowing, multipath fading and interference.

Multiple Input and Multiple Output (MIMO) is one of the approaches to

improve the data rate and reliability. In MIMO, the receiver receives the combined

signals from individual paths which are independently distributed in frequency, time

and space. This technique is known as spatial diversity which can enhance the

system performance. However, a higher cost is required to upgrade an existing base

station with the multiple antennas for MIMO.

On the other hand, wireless relay terminal offers improvement of signal

reliability and cost efficiency whereby its deployment is not relying on wired

backhaul. A relay is introduced in between source terminal, and destination terminal

to provide redundant path known as the cooperative relay link for transmission. The

conventional wireless system used a point-to-point link from the base station to the

user equipment. This link is also known as a direct link. A relay can boost the signal

reliability by combining the cooperative relay link and direct link.

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1.2 Problem Statement

The following are the problem statements for this project:

(a) Most of the existing works on cooperative relay investigate the

performance through theoretically simulation. The real world

performance remains unknown because the lack of relay prototype for

field testing and measurement.

(b) The simulations usually fail to realistically capture the real world

wireless signal propagation effects, which motivates the need of a

testbed of practical relay to access the performance in actual

environment.

1.3 Research Objectives

The objectives of the project are:

(a) to develop a cooperative relay testbed using Universal Software Radio

Peripheral (USRP) and LabView platform software.

(b) to measure the performance bit error rate (BER) performance of

cooperative and direct communication in indoor environment.

1.4 Scope

The scope of work is outlined in this section.This project covers the

development of three-node network consists of source, destination and a relay. The

cooperative relay technique used is amplify-and-forward (AF).

Besides that, the modulation will be accessed using orthogonal frequency-

division multiplexing (OFDM) mode. Scenarios consists of source, destination and

relay like single input single output (SISO) configuration, single relay network, the

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line of sight (LOS) and non line of sight (N-LOS) environments are considered.

Lastly, all the measurements perform on the downlink transmission.

1.5 Thesis Outline

The structure of the report consists of five chapters. In Chapter 1, the

introduction and overview of this project is stated.

.

In Chapter 2, the literature review on cooperative relay and AF relay and also

the benefits of using SDR in developing of wireless system is highlighted. The

hardware and software tools used in this project are discussed as well. The Related

work about the cooperative relay based either on theoretical simulations and testbed

measurements are reviewed in order to identify the research gaps.

The methodology of the project is covered in the Chapter 3. In this chapter,

the overview of the development USRP relay testbed is discussed. There are two

phases in developing the testbed. The first phase of development starts with the

direct link communication between the source and the destination. The second phase

covers the cooperative relay development, where the relay node is introduced

between the source and destination. The experimental setup and the configuration

parameters of the project is explained and the measurements of BER performance is

conducted in the indoor environment.

In Chapter 4, the results of BER performance measurement of the direct link

versus cooperative relay link communication is analysed. Discussion on whether the

relay prototype meets the requirements of the project is made.

Finally, in Chapter 5 a conclusion is drawn to summarise the main findings

of this project. Potential future works is also suggested.

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REFERENCES

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Transactions on Information Theory, vol. 25, no. 5, pp. 572–584, 1979.

[2] ITU-R, Circular letter 5/LCCE/2, Tech. Rep., March 2008.

[3] F. Akyildiz, M. Gutierrez-Estevez, C.Reyes, “The evolution to 4G cellular

systems: LTE-Advanced” Science Direct ,I.F. Akyildiz et al. / Physical

Communication 3 (2010) 217–244.

[4] A. Chakrabarti, A.Sabharwal, B. Aazhang, “Cooperative Communication:

Fundamental Limits and Practical Implementation” Cooperation in

Wireless Networks: Principles and Applications, 29–68. 2006 Springer.

[5] A. Bletsas, A. Khisti, D. Reed, and A. Lippman, “A simple cooperative

diversity method based on network path selection,” IEEE Journal on 2006

[6] P. Szilagyi , H. Sanneck “LTE relay node self-configuration”

international symposium IEEE, 2011.

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Algorithms and Architectures”, Ph.D Dissertation, Massachusetts Institute

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[10] Milica Pejanovic-Djurisic, Enis Kocan, Ramjee Prasad,” Ofdm Based Relay

Systems for Future Wireless Communication” River Publishers, 2012.

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Conference, 1992 - Digital Object Identifier 10.1109/NTC.1992.267870.

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November 2007http://www.sdrforum.org/pages/aboutSdrTech/whatIsSdr.asp

[13] D. Casey, A. Tagliarini ” Prototyping with GNU Radio and the USRP

Where to Begin” Southeastcon, IEEE 2009.

[14] Dawei Shen, "The USRP Board," August,2005. [Online]. Available:

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astro.square7.ch/Datenblaetter/gnuradiodoc-4.pdf

[15] NI USRP-292x/293x Datasheet Universal Software Radio Peripherals

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Defined Radio Testbed”, IEEE INFOCOM 2010 proceedings

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[19] Jaafar. A. Aldhaibani, A.Yahya, R.B. Ahmad ,Normaliza Omar,Zaid G.

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