configuration of multiple input multiple output antenna arrays for wireless communications in ...

212 Pages·2013·2.22 MB·English

CONFIGURATION OF MULTIPLE INPUT MULTIPLE
OUTPUT ANTENNA ARRAYS FOR WIRELESS
COMMUNICATIONS IN UNDERGROUND MINES
by
Arghavan Emami Forooshani
B.Sc., Iran University of Science and Technology, 2000
M.Sc., University of Manitoba, 2006
A THESIS SUBMITTED IN PARTIAL FULLFILLMENT OF
THE REQUIREMENTS FOR THE DEGREE OF
DOCTOR OF PHILOSOPHY
in
The Faculty of Graduate and Postdoctral Studies
(Electrical and Computer Engineering)
THE UNIVERSITY OF BRITISH COLUMBIA
(Vancouver)
August 2013
© Arghavan Emami Forooshani, 2013
ABSTRACT
In recent years, the underground mining community has begun to embrace standards-based
short-range wireless communications technology as a key part of their strategy for enhancing
the safety and productivity of their operations. Here, we show how the significant differences
between wireless propagation in conventional surface environments and underground mines
affect the design of modern wireless communications systems based upon multiple-input
multiple-output (MIMO) antenna array technology. In order to achieve this goal, we have
employed a variety of approaches to characterize wireless propagation (and MIMO-based
wireless system performance) in underground environments representative of those found in
modern hard rock mines, including: 1)field measurements collected using a custom-designed
channel sounder in both a building service tunnel at the University of British Columbia and
an underground lead-zinc mine at Myra Falls, BC, 2) simulations based upon ray-tracing in
representative environments and 3) theoretical models based upon waveguide mode
expansion in representative environments. We have used the results obtained: 1) to determine
the reduction in the angular spread of multipath signals that arrive at the receiver in an
underground mine compared to that observed in conventional surface environments and the
manner in which it decreases with increasing transmitter-receiver separation and 2) to show
that the antenna elements in MIMO antenna arrays used in underground environments must
therefore be separated by several wavelengths (rather than the customary half-wavelength
used in surface environments) in order to achieve acceptable performance. Further, the
separation between the antennas must increase as the transmitter-receiver separation
increases, higher order modes attenuate and, as a consequence, angular spread decreases.
Other outcomes of this work include: 1)demonstration that the power azimuth spectrum
(PAS) in underground mine environments can be modeled by a Gaussian distribution and
2)development of a novel technique based upon particle swarm optimization (PSO) for
assessing and optimizing the performance of distributed-MIMO antenna systems in
underground mineenvironments.
ii
PREFACE
This thesis presents research conducted by Arghavan Emami-Forooshani under the
supervision of Prof. David G. Michelson in the Radio Science Lab (RSL) at the University of
British Columbia, Vancouver campus. Prof. Sima Noghanian (University of North Dakota)
provided valuable technical suggestions and feedback during various stages of the thesis
project.
A version of Chapter 2, “A survey on wireless propagation modeling in underground
mines” has been accepted for publication in IEEE Communications Surveys and Tutorials
[manuscript ID: COMST-00130-2012-R1]. Prof. Sima Noghanian read an early draft and
provided valuable technical feedback. Shahzad Bashir suggested some revisions to the
Introduction and Conclusions.
During the development of the MIMO channel sounder in Chapter 3, Robert D. White
assisted with development of the data acquisition code.
A poster based on Chapter 4, “Effect of antenna configuration on performance of
MIMO-based access points in a service tunnel” was presented at IEEE APS/USNC-URSI
2012(Chicago, IL), in Jul. 2012 and an abstract was published in the conferenceproceedings.
A version of Chapter 5, “Effect of antenna array properties on MIMO system
performance in an underground mine,” has been accepted for publication in IET Microwave,
Antennas and Propagation [manuscript ID: MAP-2013-0102.R1]. Robert D. White
participated in the MIMO measurement campaign in the underground mine.
iii
For Chapter 6, Prof. Sima Noghanian provided valuable technical feedback
throughout the project.
iv
TABLE OF CONTENTS
Abstract.....................................................................................................................................ii
Preface.....................................................................................................................................iii
Table of Contents....................................................................................................................iii
List of Tables.........................................................................................................................viii
List of Figures.........................................................................................................................ix
Abbreviations..........................................................................................................................xii
Acknowledgements..................................................................................................................xv
Dedication.............................................................................................................................xvii
CHAPTER 1:INTRODUCTION AND OVERVIEW............................................................1
1.1 Wireless in Underground Mines........................................................................................2
1.2 Characterization of MIMO-Based Systems......................................................................5
1.3 Previous Efforts to Design Antenna Configuration in Indoor Environments...............8
1.4 Implications for MIMO Antenna Configuration Design and Deployment in
UndergroundMines.......................................................................................................................11
1.5 Objectives of This Work...................................................................................................12
1.6 Organization of the Thesis...............................................................................................12
CHAPTER 2:A SURVEY OF WIRELESS COMMUNICATIONS AND PROPAGATION
MODELING IN UNDERGROUND MINES.......................................................................14
2.1 Introduction.......................................................................................................................14
2.2 Wireless Propagation Terminology.................................................................................17
2.3 The Evolution of Wireless Communications in Tunnels and Underground Mines....22
2.4 Propagation Analysis and Modeling...............................................................................29
v
2.5 Measurement-Based Modeling........................................................................................49
2.6 Implications for Wireless Communication System Design...........................................60
2.7 Conclusions........................................................................................................................71
CHAPTER 3:MIMO EXPERIMENTAL SETUP AND DATA COLLECTION...............74
3.1 Introduction.......................................................................................................................74
3.2 Development of a MIMO Channel Sounder...................................................................74
CHAPTER 4:EFFECT OF ANTENNA CONFIGURATION ON MIMO-BASED
ACCESS POINTS IN A SHORT TUNNEL.........................................................................81
4.1 Introduction.......................................................................................................................81
4.2 Simulation Setup and Scenarios......................................................................................84
4.3 Multiple Antenna Analysis...............................................................................................89
4.4 Simulation Results and Discussions.................................................................................91
4.5 Experimental Validation................................................................................................102
4.6 Conclusions......................................................................................................................105
CHAPTER 5:EFFECT OF ARRAY PROPERTIES ON MIMO SYSTEM
PERFORMANCE IN AN UNDERGROUND MINE........................................................107
5.1 Introduction.....................................................................................................................107
5.2 MIMO Measurement in an Underground Mine..........................................................110
5.3 Multiple Antenna Analysis.............................................................................................115
5.4 Measurement Results and Discussions..........................................................................118
5.5 Conclusions......................................................................................................................129
CHAPTER 6:CHARACTERIZATION OF ANGULAR SPREAD IN UNDERGROUND
TUNNELS BASED ON A MULTIMODE WAVEGUIDE MODEL.................................131
6.1 Introduction.....................................................................................................................131
6.2 A Multimode Waveguide Model....................................................................................133
vi
6.3 Angular Spreadand Capacity Characterization Based on a Multimode Waveguide
Model ...........................................................................................................................................135
6.4 Results and Validation of Multimode Modeling..........................................................138
6.5 Extension of the IEEE 802.11n MIMO Channel Model to Underground Mines......153
6.6 Conclusions......................................................................................................................154
CHAPTER 7:OPTIMIZATION OF ANTENNA PLACEMENT IN DISTRIBUTED
MIMO SYSTEMS FOR UNDERGROUND MINES.........................................................156
7.1 Introduction.....................................................................................................................156
7.2 Multimode Waveguide Modeling and Experimental Validation................................159
7.3 Optimization of C-MIMO and D-MIMO Configurations...........................................162
7.4 Comparison of C-MIMO and D-MIMO System Performance...................................168
7.5 Conclusions......................................................................................................................178
CHAPTER 8:CONCLUSIONS..........................................................................................181
8.1 Contributions...................................................................................................................181
8.2 Recommendations for Future Work.............................................................................183
REFERENCES....................................................................................................................185
vii
LIST OF TABLES
TABLE2-1 OVERALL LOSS ALONG A STRAIGHT PATH(E MODE WITH HALF-WAVE ANTENNAS)[11]..................38
H
TABLE2-2 OVERALL LOSS ALONG APATH INCLUDING ONE CORNER(E MODE WITH HALF-WAVE ANTENNAS)
H
[11]. ...........................................................................................................................................................38
TABLE2-3 COMPARISONOF DIFFERENT ANALYTICAL MODELS............................................................................48
TABLE2-4 SOME SIMILARITIES ANDDIFFERENCES BETWEENUNDERGROUND MINES,STRAIGHT LONG TUNNELS
AND CONVENTIONAL INDOOR FOR PROPAGATIONATUHF-BAND(F:FREQUENCY,N:PATHLOSS EXPONENT,
ΤRMS:RMSDELAY SPREAD,DTX-RX:TX ANDRX DISTANCE,↑:INCREASE,↓:DECREASE)................................52
TABLE2-5 PATHLOSS EXPONENT ANDDELAY SPREAD ASSUMING OMNI-DIRECTIONAL ANTENNASFOR SEVERAL
FREQUENCIES IN DIFFERENT ENVIRONMENTS...............................................................................................55
TABLE2-6 KEY IMPLICATIONS FORWIRELESS SYSTEM DESIGN ATUHF-BAND IN UNDERGROUNDMINES...........71
TABLE3-1 MEASUREMENT SPECIFICATIONS........................................................................................................76
TABLE4-1 SPECIFICATIONS OF THEMAIN STRUCTURES USEDINTHEWIRELESSINSITE SIMULATIONS................86
TABLE4-2 DIFFERENT ANTENNA CONFIGURATION AND DEPLOYMENT SCENARIOS(X:PARALLEL TO THE TUNNEL
WIDTH,Y:PARALLEL TO THE TUNNEL HEIGHT,LONG:PARALLEL TO THE TUNNEL AXIS,H:HORIZONTAL
POLARIZATION ANDV:VERTICAL POLARIZATION)......................................................................................88
TABLE4-3 CORRELATION COEFFICIENT OF NEIGHBORING ELEMENTS ATRX WITH DIFFERENT INTERELEMENT
SEPARATIONS(V:VERTICAL,H:HORIZONTAL POLARIZATIONS)..................................................................93
TABLE4-4 AVERAGE PATHLOSS AT2.49GHZ...................................................................................................100
TABLE4-5 MEASUREMENT SPECIFICATIONS......................................................................................................102
TABLE4-6 CAPACITY STATISTICS AT2.49GHZ ANDSNR=20DBTO COMPAREMIMOCAPACITY OF DIFFERENT
ANTENNA CONFIGURATIONS(WITH POWER-IMPACT).................................................................................103
TABLE5-1 MIMOMEASUREMENT SCENARIOS IN THEMYRAFALLS UNDERGROUND MINE...............................114
TABLE5-2 ENVELOPE CORRELATIONCOEFFICIENTS OFRX GRID ANTENNAS FORDIFFERENT MEASUREMENT
SCENARIOS(F=2.49GHZ)..........................................................................................................................115
TABLE5-3 SINGULAR VALUES OF MEASUREDH-MATRICES AND I.I.D.RAYLEIGHH-MATRICES(ALL SINGULAR
VALUES ARE NORMALIZED TO THE LARGEST ONE).....................................................................................121
TABLE5-4 MEAN PATHLOSS MEASURED AT EACHRX GRID LOCATION INMYRA-FALLS MINE(AT2.49GHZ)..128
TABLE6-1 ANGULAR SPREADS(DEG)FOR DIFFERENT ZONESOF THE LARGE AND SMALL TUNNEL OBTAINED BY
MULTIMODE AND RAY-TRACING METHODS................................................................................................142
TABLE6-2 COMPARISON OFASFOR DIFFERENT ENVIRONMENTS.....................................................................146
TABLE6-3 MEDIAN AND10%OUTAGE4×4MIMOCAPACITY(BIT/SEC/HZ)ATSNR=20DBFOR SEVERAL
INTERELEMENT SPACINGS AND DIFFERENT ZONES OF THE SMALL TUNNEL.................................................153
TABLE7-1 MULTIMODE ANDPSOSIMULATION SETUP......................................................................................169
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LIST OF FIGURES
FIGURE1-1 TECHNOLOGY PUSH INTOMINING UNDERGROUND MINES OVER TIME..............................................4
FIGURE1-2 DIFFERENT TYPES OFMIMOANTENNA CONFIGURATIONS,SUCH ASULAANDUCAFOR INDOOR
ENVIRONMENTS...........................................................................................................................................10
FIGURE1-3 FIXEDTXULAPLACED ON THE PLATFORM,MOBILERXULAINSTALLED ON THE TRAIN
WINDSHIELD[21].........................................................................................................................................11
FIGURE2-1 WIRELESS PROPAGATIONPHENOMENA..........................................................................................18
FIGURE2-2 LARGE-SCALE AND SMALL-SCALE FADINGS..................................................................................19
FIGURE2-3 APATHLOSS MODEL WITHTHREE BREAKPOINTS...........................................................................21
FIGURE2-4 THROUGH-THE-EARTH COMMUNICATIONS....................................................................................24
FIGURE2-5 LEAKY FEEDER CABLE...................................................................................................................26
FIGURE2-6 TRACKING SYSTEM IN ANUNDERGROUND MINE[52].....................................................................27
FIGURE2-7 SURFACE ANTENNA FOR THROUGH-THE-EARTH COMMUNICATIONS..............................................30
FIGURE2-8 A)CURRENT DISTRIBUTIONAND ELECTRIC FIELD LINES OF THE MONOFILAR MODE(BETWEEN EACH
WIRE AND THE TUNNELWALL)AND B)MONOFILAR MODE AND BIFILAR MODE(BETWEEN THE WIRES)[30].32
FIGURE2-9 COMPARISON OF REFLECTION ANGLES OF LOWERAND HIGHER ORDER MODES IN A WAVEGUIDE..34
FIGURE2-10 MAP AND DIGITAL PHOTOGRAPH OF AN UNDERGROUND GALLERY[60]........................................35
FIGURE2-11 OVERALL LOSS FOR VARIOUS DISTANCES ALONGA STRAIGHT TUNNEL FOR HALF-WAVE ANTENNAS
WITH HORIZONTAL POLARIZATIONS(ZISTX-RX DISTANCE)[11]................................................................37
FIGURE2-12 MEASURED DATA FOR TWOPOLARIZATIONS AT900MHZ TOGETHER WITH THETWO-SLOPE
REGRESSION FITS IN ACOAL MINE[74]........................................................................................................41
FIGURE2-13 STOCHASTIC SCATTERINGAPPROACH:REFLECTION AT RANDOMLY ORIENTED TANGENTIAL PLANES
FOR EACH DISCRETE RAY(A)SAME PLANE FOR ALL THE RAYS AND(B)RANDOMLY ORIENTED PLANES[87]...
......................................................................................................................................................47
FIGURE2-14 (A)ARECTANGULAR WAVEGUIDE AND(B)CIMMODEL FOR THE WAVEGUIDE INFIGURE(A)[88]...
......................................................................................................................................................47
FIGURE2-15 RADIUS OF A CURVATUREIN A RECTANGULAR CURVED TUNNEL[13]...........................................64
FIGURE3-1 BLOCK DIAGRAM OF THEMEASUREMENT SETUP............................................................................76
FIGURE3-2 MIMOMEASUREMENT EQUIPMENTINRSL..................................................................................77
FIGURE3-3 CONNECTION DIAGRAM FOR CALIBRATION....................................................................................79
FIGURE3-4 FLOWCHART OF THEUWB-MIMOCHANNEL SOUNDER SOFTWARE..............................................80
FIGURE4-1 UBCWOODWARD SERVICE TUNNEL CONSTRUCTED INWIRELESSINSITE WITH ITS EXTENSIVE
INFRASTRUCTURE AND CONSIDERING3PROPAGATION SCENARIOS..............................................................85
ix
FIGURE4-2 ANTENNA CONFIGURATIONSCENARIOS USED IN THIS STUDY(V:VERTICAL,H:HORIZONTAL).....89
FIGURE4-3 COMPARISON OF DIFFERENT ANTENNA CONFIGURATIONS FOR THE TUNNELWITHOUT
INFRASTRUCTURE........................................................................................................................................96
FIGURE4-4 COMPARISON OF THE PERFORMANCE OF TR-X-VAND TR-Y-HANTENNA CONFIGURATIONS ATRX2.
......................................................................................................................................................96
FIGURE4-5 COMPARISON OF DIFFERENT ANTENNA CONFIGURATIONS FOR THE TUNNELWITH
INFRASTRUCTURE........................................................................................................................................97
FIGURE4-6 IMPACT OF INFRASTRUCTURE ON PERFORMANCE OF TR-X-V-SC6ANTENNA CONFIGURATION......99
FIGURE4-7 COMPARISON OF SIMULATED(WITH INFRASTRUCTURE)AND MEASUREDMIMOCAPACITYCDFS...
....................................................................................................................................................104
FIGURE5-1 MAP OF THEMYRA-FALLS MINE INB.C.,CANADA AND THE TRANSMITTING(TX)ARRAY AND
RECEIVER(RX)GRID LOCATIONS(5TX ARRAY LOCATIONS AND2RX GRID LOCATIONS)..........................111
FIGURE5-2 PHOTOGRAPHY OFRFEQUIPMENT INMYRAFALLS MINE...........................................................111
FIGURE5-3 SPATIAL CORRELATION ANALYSIS ON THE SUCCESSIVE ANTENNA ELEMENTS ON THERX GRID FOR
TWO DIFFERENT ARRAYORIENTATIONS:(A)PERPENDICULAR TO THETUNNEL AXIS AND(B)PARALLEL TO
THE TUNNEL AXIS......................................................................................................................................114
FIGURE5-4 CDFS OF4×4-MIMOCAPACITY WITHOUT POWER CONSIDERATIONS(BASED ON THE
MEASUREMENT).........................................................................................................................................119
FIGURE5-5 ANGULAR SPREAD VARIATION VERSUS DISTANCE(BASED ON MULTIMODE WAVEGUIDE MODEL).....
....................................................................................................................................................122
FIGURE5-6 CAPACITY OF4×4-MIMOSYSTEM FOR DIFFERENTANTENNA SPACINGS(BASED ON THE
MULTIMODE WAVEGUIDEMODEL).............................................................................................................123
FIGURE5-7 CDFS OF4×4-MIMOCAPACITY WITH POWERCONSIDERATIONS(BASED ON THE MEASUREMENT)...
....................................................................................................................................................124
FIGURE5-8 ATUNNEL WITH RECTANGULAR CROSS-SECTION.........................................................................126
FIGURE5-9 CDFS OF4×4-MIMOCAPACITY WITH POWERCONSIDERATIONS(BASED ON MEASUREMENTAND
MULTIMODE WAVEGUIDEMODEL ATF=2.49GHZ,SNR=20DB)..............................................................129
FIGURE6-1 COMPARISON OF MULTIMODE MODEL WITH EXPERIMENTAL WORK OBTAINEDFROM[13]...........135
FIGURE6-2 REFLECTION ANGLES OFLOWER AND HIGHER ORDER MODES FROM SIDEWALLS IN A WAVEGUIDE
(Φ1IS THE ANGLE FOR THELOWER ORDER ANDΦ2IS FOR THE HIGHER ORDER MODE)................................136
FIGURE6-3 THE CROSS-SECTION OF THE SUBWAY TUNNEL AND ITS EQUIVALENT RECTANGLE.....................139
FIGURE6-4 ZERO-MEANGAUSSIAN FIT OF THEPASFOR THE SMALL TUNNEL(MULTIMODE WAVEGUIDE
MODEL). ....................................................................................................................................................140
FIGURE6-5 ZERO-MEANGAUSSIAN FIT OF THEPASFOR DIFFERENT ZONESOF TWO TUNNEL SIZES
(MULTIMODE WAVEGUIDEMODEL)............................................................................................................141
FIGURE6-6 COMPARISON OFPASOBTAINED BY MULTIMODE AND RAY-TRACING FOR THE SMALL TUNNEL
(WHOLE TUNNEL).......................................................................................................................................142
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