Automotive Informatics and Communicative Systems Principles in Vehicular Networks and Data Exchange

Automotive Informatics
and Communicative
Systems:
Principles in Vehicular
Networks and Data Exchange
Huaqun Guo
Institute for Infocomm Research, A*STAR, Singapore
Hershey • New York
InformatIon scIence reference
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Library of Congress Cataloging-in-Publication Data
Automotive informatics and communicative systems : principles in vehicular
networks and data exchange / Huaqun Guo, editor.
p. cm.
Includes bibliographical references and index.
Summary: "This book advances the understanding of management methods, information technology, and their joint application in business
processes" Provided by publisher.
ISBN 978-1-60566-338-8 (hardcover) ISBN 978-1-60566-367-8 (ebook) 1. Automobile industry and trade Management. 2.
Information technology. I. Guo, Huaqun, 1967- HD9710.A2A8725 2009 388.3'12 dc22
200805016
British Cataloguing in Publication Data
A Cataloguing in Publication record for this book is available from the British Library.
All work contributed to this book is new, previously-unpublished material. The views expressed in this book are those of the authors, but not
necessarily of the publisher.
Editorial Advisory Board
Lawrence Wai-Choong Wong, National University of Singapore, Singapore
Weihua Zhuang, University of Waterloo, Canada
Ozan K. Tonguz, Carnegie Mellon University, USA
Javier Ibañez-Guzmán, RENAULT S.A.S., France
Todd Hubing, Clemson University, USA
Nicholas F. Maxemchuk, Columbia University, USA
Farid Naït-Abdesselam, University of Sciences and Technologies of Lille, France
Yul Chu, University of Texas–Pan American, USA
List of Reviewers
Sohel Anwar, Indiana University Purdue University Indianapolis, USA

Raúl Aquino-Santos, Universidad de Colima, México
Teck Yoong Chai, Institute for Infocomm Research, A*STAR, Singapore
Yul Chu, University of Texas–Pan American, USA
Gavin Holland, HRL Laboratories, LLC., USA
Todd Hubing, Clemson University, USA
Javier Ibañez-Guzmán, RENAULT S.A., France
Tie Yan Li, Institute for Infocomm Research, A*STAR, Singapore
Nicholas F. Maxemchuk, Columbia University, USA
Farid Naït-Abdesselam, University of Sciences and Technologies of Lille, France
Lek Heng Ngoh, Institute for Infocomm Research, A*STAR, Singapore
Fabienne Nouvel, Laboratory IETR/INSA, France
Stephan Olariu, Old Dominion University, USA
Vasudha Ramnath, Institute for Infocomm Research, A*STAR, Singapore
Biplab Sikdar, Rensselaer Polytechnic Institute, USA
Joseph Chee Ming Teo, Institute for Infocomm Research, A*STAR, Singapore
Satish Ukkusuri, Rensselaer Polytechnic Institute, USA
Ziyuan Wang, University of Melbourne, Australia
Lawrence Wai-Choong Wong, National University of Singapore, Singapore
Yew Fai Wong, National University of Singapore, Singapore
Zonghua Zhang, National Institute of Information and Communication Technology, Japan
Weihua Zhuang, University of Waterloo, Canada
Foreword xiii
Preface xv
Acknowledgment xxi
Chapter I
Introduction: An Emerging Area of Vehicular Networks and Data Exchange 1
Huaqun Guo, Institute for Infocomm Resear
ch, A*STAR, Singapore
Chapter II
Drive by W

ire Systems: Impact on Vehicle Safety and Performance 12
Sohel Anwar, Indiana University-Purdue University Indianapolis, USA
Chapter III
Electromagnetic Compatibility Issues in Automotive Communications 48
T
odd H. Hubing, Clemson University International Center for Automotive Research, USA
Chapter IV
Automotive Network Architecture for ECUs Communications 69
Fabienne Nouvel, Laboratory IETR-UMR, INSA, France
W
ilfried Gouret, Laboratory IETR-UMR, INSA, France
Patrice Mazério, Laboratory IETR-UMR, INSA, France
Ghais El Zein, Laboratory IETR-UMR, INSA, France
Chapter V
Enabling Secure Wireless Real-T
ime Vehicle Monitoring and Control 91
Lek Heng Ngoh, Institute for Infocomm Research, A*STAR, Singapore
Chapter VI
MAC and Routing Protocols for
Vehicle to Vehicle Communications 105
Xiaobo Long, Rensselaer Polytechnic Institute, USA
Biplab Sikdar, Rensselaer Polytechnic Institute, USA
Table of Contents
Chapter VII
Inter-Vehicular Communications Using Wireless Ad Hoc Networks 120
Raúl Aquino-Santos, University of Colima, Mexico
Víctor Rangel-Licea, National Autonomous University of Mexico, Mexico
Miguel A. García-Ruiz, University of Colima, Mexico
Apolinar González-Potes, University of Colima, Mexico
Omar Álvarez-Cardenas, University of Colima, Mexico

Arthur Edwar
ds-Block, University of Colima, Mexico
Margarita G. Mayoral-Baldivia, University of Colima, Mexico
Sara Sandoval-Carrillo, University of Colima, Mexico
Chapter VIII
The Role of Communications in Cyber-Physical Vehicle Applications 139
Nicholas F. Maxemchuk, Columbia University, USA & IMDEA Networks, Spain
Patcharinee Tientrakool, Columbia University, USA
Theodore L. Willke, Columbia University, USA & Intel Corporation, USA
Chapter IX
Integrating Trafc Flow Features to Characterize the Interference in Vehicular Ad Hoc
Networks 162
Lili Du, Pur
due University, USA
Satish Ukkusuri, Rensselaer Polytechnic Institute, USA
Shivkumar Kalyanaraman, Rensselaer Polytechnic Institute, USA
Chapter X
Proactive Trafc Merging Strategies for Sensor-Enabled Cars
180
Ziyuan W
ang, University of Melbourne, Australia
Lars Kulik, University of Melbourne, Australia
Kotagiri Ramamohanarao, University of Melbourne, Australia
Chapter XI
The Localisation Problem in Cooperative V
ehicle Applications 200
Javier Ibañez-Guzmán, RENAUL
T S.A.S., France
Chapter XII
An Overview of Positioning and Data Fusion Techniques Applied to Land

Vehicle
Navigation Systems 219
Denis Gingras, Université de Sherbrooke, Canada
Chapter XIII
Efcient and Reliable Pseudonymous Authentication 247
Giorgio Calandriello, Politecnico di Torino, Italy
Antonio Lioy, Politecnico di T
orino, Italy
Chapter XIV
Simulation of VANET Applications 264
Valentin Cristea, University Politehnica of Bucharest, Romania
V
ictor Gradinescu, University Politehnica of Bucharest, Romania
Cristian Gorgorin, University Politehnica of Bucharest, Romania
Raluca Diaconescu, University Politehnica of Bucharest, Romania
Liviu Iftode, Rutgers University, USA
Chapter
XV
In-Vehicle Network Architecture for the Next-Generation Vehicles 283
Syed Masud Mahmud, Wayne State University, USA
Compilation of References 303
About the Contributors 330
Index 338
Foreword xiii
Preface xv
Acknowledgment xxi
Chapter I
Introduction: An Emerging Area of Vehicular Networks and Data Exchange 1
Huaqun Guo, Institute for Infocomm Resear
ch, A*STAR, Singapore

This chapter gives
an overview of this emerging area of vehicular networks, its potential applications,
its potential wireless technologies for data exchange, and its research activities in the Europe, the United
States (U.S.), Japan, and Singapore.
Chapter II
Drive by Wire Systems: Impact on Vehicle Safety and Performance 12
Sohel Anwar, Indiana University-Purdue University Indianapolis, USA
An overview of the
drive-by-wire technology is presented along with in-depth coverage of salient drive
by systems such as throttle-by-wire, brake-by-wire, and steer-by-wire systems, and hybrid-electric propul-
sion. A review of drive-by-wire system benets in performance enhancements and vehicle active safety is
then discussed. This is followed by in-depth coverage of technological challenges that must be overcome
before drive-by-wire systems can be production ready. Current state of the art of possible solutions to
these technological hurdles is then discussed. Future trends in the drive-by-wire systems and economic
and commercialization aspects of these system are presented at the conclusion of the chapter.
Chapter III
Electromagnetic Compatibility Issues in Automotive Communications 48
T
odd H. Hubing, Clemson University International Center for Automotive Research, USA
Detailed Table of Contents
This chapter reviews automotive EMC requirements and discusses the design of automotive electron-
ics for EMC. The objective of the chapter is to provide non-EMC engineers and engineering managers
with basic information that will help them recognize the importance of designing for electromagnetic
compatibility, rather than addressing electronic noise problems as they arise.
Chapter IV
Automotive Network Architecture for ECUs Communications 69
Fabienne Nouvel, Laboratory IETR-UMR, INSA, France
W
ilfried Gouret, Laboratory IETR-UMR, INSA, France
Patrice Mazério, Laboratory IETR-UMR, INSA, France

Ghais El Zein, Laboratory IETR-UMR, INSA, France
This chapter introduces the most
widely used automotive networks like LIN (Local Interconnect Net-
work), CAN (Controller Area Network), MOST (Media-Oriented Systems Transport), and FlexRay.
To fulll the increasing demand of intra-vehicle communications, a new technique based on power
line communication (PLC) is then proposed. This allows the transmission of both power and messages
without functional barriers. On the other hand, there are several infotainment applications (like mobile
phones, laptop computers) pushing for the adoption of intra-vehicle wireless communications. Thus,
some potential wireless technologies used in the automotive domain, namely Bluetooth, IEEE 802.11
b/g wireless technology – WiFi, and Zigbee are covered here. Finally, the chapter highlights the chal-
lenges of these wired or wireless alternative solutions in automotive networks.
Chapter V
Enabling Secure Wireless Real-Time Vehicle Monitoring and Control 91
Lek Heng Ngoh, Institute for Infocomm Resear
ch, A*STAR, Singapore
In
this chapter, the author extends the use of these embedded vehicular networks by proposing to remotely
monitor and control the vehicles through them, in order to realize safety and driver assistance related
applications. To accomplish this task, additional technologies such as real-time wireless communications
and data security are required, and each of them is introduced and described in this chapter.
Chapter VI
MAC and Routing Protocols for Vehicle to Vehicle Communications 105
Xiaobo Long, Rensselaer Polytechnic Institute, USA
Biplab Sikdar, Rensselaer Polytechnic Institute, USA
Numerous efforts are currently under
progress to enhance the safety and efciency of vehicular trafc
through intelligent transportation systems. In addition, the growing demand for access to data and infor-
mation from human users on the go has created the need for advanced vehicle-to-vehicle and vehicle-
to-roadside communication systems capable of high data rates and amenable to high degrees of node
mobility. Vehicular communications and networks are expected to be used for a number of purposes such

as for enabling mobile users to transfer data and information from other networks such as the Internet
and also for implementing services such as Intersection Decision Systems (IDS), Automated Highway
Systems (AHS), and Advanced Vehicle Safety Systems (AVS). In this chapter the authors describe me-
dium access control (MAC) and routing protocols for vehicular networks and the various factors that
affect their design and performance.
Chapter VII
Inter-Vehicular Communications Using Wireless Ad Hoc Networks 120
Raúl Aquino-Santos, University of Colima, Mexico
Víctor Rangel-Licea, National Autonomous University of Mexico, Mexico
Miguel A. García-Ruiz, University of Colima, Mexico
Apolinar González-Potes, University of Colima, Mexico
Omar Álvarez-Cardenas, University of Colima, Mexico
Arthur Edwar
ds-Block, University of Colima, Mexico
Margarita G. Mayoral-Baldivia, University of Colima, Mexico
Sara Sandoval-Carrillo, University of Colima, Mexico
This chapter proposes a new routing algorithm that allows communication in vehicular ad hoc networks.
In vehicular ad hoc networks, the transmitter node cannot determine the immediate future position of the
receiving node beforehand. Furthermore, rapid topological changes and limited bandwidth compound
the difculties nodes experience when attempting to exchange position information.
Chapter VIII
The Role of Communications in Cyber-Physical Vehicle Applications 139
Nicholas F. Maxemchuk, Columbia University, USA & IMDEA Networks, Spain
Patcharinee Tientrakool, Columbia University, USA
Theodor
e L. Willke, Columbia University, USA & Intel Corporation, USA
The authors describe applications that improve the operation of automobiles, control trafc lights, and
distribute the load on roadways. The requirements on the communications protocols that implement the ap-
plications are determined and a new communications paradigm, neighborcast, is described. Neighborcast
communicates between nearby entities, and is particularly well suited to transportation applications.

Chapter IX
Integrating Trafc Flow Features to Characterize the Interference in Vehicular Ad Hoc
Networks 162
Lili Du, Pur
due University, USA
Satish Ukkusuri, Rensselaer Polytechnic Institute, USA
Shivkumar Kalyanaraman, Rensselaer Polytechnic Institute, USA
The research in this chapter
investigates several fundamental issues, such as the connectivity, the reach-
ability, the interference, and the capacity, with respect to information propagation in VANETs. The authors’
work is distinguished with previous efforts, since they incorporate the characteristics of trafc into these
issues in the communication layer of VANETs; this mainly address the issue of the interference. Previous
efforts to solve this problem only consider static network topologies. However, high node mobility and
dynamic trafc features make the interference problem in VANETs quite different.
Chapter X
Proactive Trafc Merging Strategies for Sensor-Enabled Cars 180
Ziyuan Wang, University of Melbourne, Australia
Lars Kulik, University of Melbourne, Australia
Kotagiri Ramamohanarao, University of Melbourne, Australia
This chapter surveys trafc control
strategies for optimizing trafc ow on highways, with a focus on
more adaptive and exible strategies facilitated by current advancements in sensor-enabled cars and
vehicular ad hoc networks (VANETs). The authors investigate proactive merging strategies assuming
that sensor-enabled cars can detect the distance to neighboring cars and communicate their velocity and
acceleration among each other. Proactive merging strategies can signicantly improve trafc ow by
increasing it up to 100% and reduce the overall travel delay by 30%.
Chapter XI
The Localisation Problem in Cooperative Vehicle Applications 200
Javier Ibañez-Guzmán, RENAUL
T

S.A.S., France
In this chapter, V2V
and V2I applications are considered as a spatio-temporal problem. The tenet is that
sharing information can be made only if this is time stamped and related to a spatial description of the in-
formation sources. The chapter formulates the spatio-temporal problem having as constraint the precision
of the pose estimates of the vehicles involved. It regards the localisation problem and accuracy of digital
road maps as a combined issue that needs to be addressed for the successful deployment of cooperative
vehicle applications. Two case studies, intersection safely and an overtaking manoeuvre are included.
Recommendations on the precision limits of the vehicle pose estimations and the potential uncertainties
that need to be considered when designing V2V and V2I applications complete the chapter.
Chapter XII
An Overview of Positioning and Data Fusion Techniques Applied to Land Vehicle
Navigation Systems 219
Denis Gingras, Université de Sherbr
ooke, Canada
In this chapter, the authors
will review the problem of estimating in real-time the position of a vehicle
for use in land navigation systems. After describing the application context and giving a denition of the
problem, they will look at the mathematical framework and technologies involved to design positioning
systems. The authors will compare the performance of some of the most popular data fusion approaches
and provide some insights on their limitations and capabilities.
Chapter XIII
Efcient and Reliable Pseudonymous Authentication 247
Gior
gio Calandriello, Politecnico di Torino, Italy
Antonio Lioy, Politecnico di Torino, Italy
Pri
vacy, security, and reliability are key requirements in deploying vehicular ad-hoc networks (VANET).
Without those the VANET technology will not be suitable for market diffusion. In this chapter, the au-
thors are concerned with how to fulll these requirements by using pseudonym-based authentication,

designing security schemes that do not endanger transport safety while maintaining low overhead. At
the same time the design improves the system usability by allowing nodes to self-generate their own
pseudonyms.
Chapter XIV
Simulation of VANET Applications 264
Valentin Cristea, University Politehnica of Bucharest, Romania
V
ictor Gradinescu, University Politehnica of Bucharest, Romania
Cristian Gorgorin, University Politehnica of Bucharest, Romania
Raluca Diaconescu, University Politehnica of Bucharest, Romania
Liviu Iftode, Rutgers University, USA
This
chapter systematically presents actual issues regarding the simulation of VANET applications.
Some of them refer to challenges in developing VANET simulators. The chapter discusses simulator
architectures, models used for representing the communication among vehicles, vehicles mobility fea-
tures, and simulation tool implementation methods. A critical analysis of the solutions adopted in some
well-known actual simulators is also included.
Chapter XV
In-Vehicle Network Architecture for the Next-Generation Vehicles 283
Syed Masud Mahmud, Wayne State University, USA
This book chapter describes a number of ways using which the networks of future vehicles could be
designed and implemented in a cost-effective manner. The book chapter also shows how simulation
models can be developed to evaluate the performance of various types of in-vehicle network topologies
and select the most appropriate topology for given requirements and specications.
Compilation of References 303
About the Contributors 330
Index 338
xiii
Foreword
Huaqun Guo has introduced the emerging areas of vehicular networks in the forms of Intra-Vehicle, Vehicle-

to-Vehicle, and Vehicle-to-Infrastructure communications and edited this new book to reect the advance
information technologies that shape the modern automobiles. These new technologies on automotive infor-
matics and communicative systems will enable a variety of applications for safety, trafc efciency, driver
assistance, as well as infotainment to be incorporated into modern automobile designs.
Over the last century, the design, manufacture and operation of the automobile have grown into complex
system integration paradigms cutting across applications of traditional disciplines in physical sciences, en-
gineering, social and behavioral sciences and business. Today, this complexity is compounded and acceler-
ated by the advent of enabling technologies in advanced materials, sensing, actuation, computing, controls,
diagnostics, electronics and software, all amid myriad – and often conicting – policy changes. This creates
new possibilities and challenges in simultaneously providing effective means of transportation - with a high
degree of driver and occupant safety - along with reduced energy use and environmental impact.
Informatics, telematics, electronics and communication systems play an ever increasing role in the ad-
vancement of the automobile and are critical from a number of perspectives. The advances that are most
easily noticed by a consumer are vehicle options such as infotainment systems, navigation systems, and con-
nectivity such as Bluetooth. However, other onboard systems such as active stability control, engine control,
and the several supporting in-vehicle communication networks and protocols are the real technologies that
are propelling the automobile into the 21st Century. Such systems are key elements in achieving the desired
operational characteristics of the vehicle such as performance, emissions, safety and fuel efciency. To achieve
these ever more stringent desired characteristics in a cost effective manner, the amount of information and
processing that occurs on a typical vehicle is staggering. Most vehicles today have well over 50 processors
on board, and the number continues to grow. Indeed, electronics can account for over 40% of the vehicle’s
cost and this percentage will continue to grow.
Onboard systems are only part of the explosion of automotive informatics and commutations. Infrastruc-
ture -to-vehicle and vehicle-to-vehicle communicants are enabling a host of new frontiers related to safety,
trafc control and maintenance. Onboard navigation systems can now route an individual vehicle through
signicant trafc jams or disruptions. However, in the near future, coordinated efforts between the trafc
infrastructure and multiple vehicles may distribute the trafc load to minimize congestion or the effects of
construction or a trafc accident. Furthermore, information from adjacent vehicles may be used to avoid
collisions. For example, vehicles that are rapidly decelerating on a highway might warn subsequent cars of
an impending “stopped trafc hazard.” From a maintenance perspective, connectivity has already enabled

the vehicle to communicate its health status and potential failures to service personnel. Such information is
not only critical to keep a vehicle functioning properly, but also enables eet manufacturers to track potential
problems, and address them as rapidly as possible. Furthermore, this information can easily and rapidly be
utilized in improving next generation vehicles.
xiv
For both onboard systems and supporting infrastructure systems, the acceleration of technological change
is driving vehicle designers, manufacturers and consumers to rethink how the automobile is developed from
conceptualization to production to service to end of life. The rapidly changing electronics and informatics
sector has pushed vehicle system design and integration to a new level of agility. The consumer desires
state-of-the-art capabilities, and automobile producers no longer have several years to incorporate the latest
technology into their products. This is fostering a change in the way vehicles are designed and perceived.
Indeed, if one looks at the automobile, it is changing rapidly and the pace of change is ever increasing. The
car of today is vastly different from its predecessors of 30 or 40 years ago, and next generation vehicles will
continue to change dramatically driven by multiple issues of which many are related to informatics and com-
munication systems.
This book has provided fundamental principles, as well as practice, and new research/trend for vehicular
networks and advanced information technologies applied in the automotive area. First, this book presents the
impact of drive-by-wire systems on vehicle safety and performance, and electromagnetic compatibility issues
affecting automotive communications. It then introduces Intra-vehicle networks like LIN (Local Interconnect
Network), CAN (Controller Area Network), MOST (Media-Oriented Systems Transport), Flexray, power-
line communication, and so forth. It also describes in-vehicle network architecture for the next-generation
vehicles and elaborates the potential applications and related technical challenges in achieving secure remote
monitoring and control of vehicles via CAN.
Second, this book presents the technologies related to Vehicle-to-Vehicle, and Vehicle-to-Infrastructure
communications by describing the current medium access control (MAC) and routing protocols for vehicular
networks, and the role of communications in cyber-physical vehicle applications. Furthermore, it incorporates
the characteristics of trafc ow into the interference issue in the communication layer of VANETs (Vehicular
Ad Hoc Networks), and presents new research into proactive trafc merging algorithms and the potential
benets of applying sensor-enabled cars. The book has also captured the state-of-the-art in the area of trafc
control with the assistance of VANETs, and reviewed the problem of estimating in real-time the position of

a vehicle for use in land navigation system.
Last but not least, privacy, security and reliability as key requirements in deploying VANETs are addressed,
as well as simulation architectures and simulation tools implementation methods with the aim to improve the
trafc safety and control. Through all chapters, this book has discussed the future trends for the automotive
informatics and communicative systems in each individual domain.
I highly recommend Dr. Guo’s timely book. I believe it will benet many readers and be a good refer-
ence.
Thomas R. Kurfess
International Center for Automotive Research, Clemson University, USA
Thomas R. Kurfess received his SB, SM and PhD degrees in mechanical engineering from M.I.T. in 1986, 1987 and 1989,
respectively. He also received an SM degree from MIT in electrical engineering and computer science in 1988. Following graduation,
he joined Carnegie Mellon University where he rose to the rank of associate professor. In 1994 he moved to the Georgia Institute of
Technology where he rose to the rank of Professor in the George W. Woodruff School of Mechanical Engineering. In 2005 he was
named Professor and BMW Chair of Manufacturing in the Department of Mechanical Engineering at Clemson University. He is also
the Director of the Campbell Graduate Engineering Center at Clemson University’s International Center for Automotive Research.
He has served as a special consultant of the United Nations to the Government of Malaysia in the area of applied mechatronics and
manufacturing, and as a participating guest at the Lawrence Livermore National Laboratory in their Precision Engineering
Program. His research focuses on the design and development of advanced systems targeting the automotive sector (OEM
and supplier) including vehicle and production systems. He has signi.cant experience in high precision manufacturing and
metrology systems. He has received numerous awards including a National Science Foundation (NSF) Young Investigator
Award, an NSF Presidential Faculty Fellowship Award, the ASME Pi Tau Sigma Award, SME Young Manufacturing Engineer
of the Year Award, the ASME Blackall Machine Tool and Gage Award, the ASME Gustus L. Larson Award. He is a Fellow of
the SME and of the ASME.
xv
Preface
The automotive industry is undergoing a continuous transformation; vehicles are no longer thermo me-
chanical systems with some electronic components used to start engines and lighting. Today’s vehicles
are complex systems, with networks of computers controlling their most important functions. Increas-
ing fuel costs, as well as increasing awareness of vehicular pollution and noise affecting large human
agglomerations and unacceptable numbers of trafc accidents and road congestion are exerting much

pressure for change on the automotive industry. What kind of change is expected?
Within a short period, mobile communications have changed our lifestyles allowing us to exchange
information, almost anywhere at anytime. The introduction of such mobile communications systems
in motor vehicles should be therefore only a matter of time. This should bring a new paradigm, that of
sharing information amongst vehicles and infrastructure, and lead to numerous applications for safety,
trafc efciency as well as infotainment.
The main purpose of this book is to provide an overview of the information and communications
technologies that are to be deployed in the new generations of vehicles – to provide valuable insights
into the technologies for vehicular networks and data exchange, from both theoretical and practical
perspectives. We hope that the contents can be used in graduate level courses as a reference and by the
automotive industry as training material. The book should provide a concise background and a good
foundation to students entering the eld of automotive information and communications technologies.
We also hope that it would serve as a reference to researchers/scientists and practitioners by enabling
them to offer exciting and novel technologies and applications that would, in the future, transform our
land transportation systems.
Information technology is the driving force behind innovations in the automotive industry. In the
past years, control systems of cars have moved from the analog to the digital domain. In particular, x-
by-wire systems began to appear, and have driven research efforts of the whole automotive industry in
the last decade. Networked Electronic Control Units (ECUs) are increasingly being deployed in cars to
realize diverse functions such as engine management, air-bag deployment, and even in intelligent brake
systems. At the same time, emerging vehicular networks in the forms of intra-vehicle, vehicle-to-vehicle
and vehicle-to-infrastructure communications are fast becoming a reality. They will enable a variety of
applications for safety, trafc efciency, driver assistance, as well as infotainment to be incorporated
into modern automobile designs.
This book introduces the advanced information technologies that shape the ultra-modern automo-
tive industry today. Contributions to this publication are made by professors, researchers, scientists
and practitioners throughout the world, bringing together their rich expertise and results of their cur-
rent endeavors. The authors have several years of expertise in their respective domains, and have good
publication records.
xvi

As can be seen from the table of contents, the book comprises of 15 chapters. It spreads across many
technical areas with car communications as the central theme. The rst chapter is an introductory chap-
ter on the emerging area of vehicular networks in the forms of Intra-Vehicle (InV), Vehicle-to-Vehicle
(V2V), and Vehicle-to-Infrastructure (V2I) communications. Chapters II to III and a large part of Chapter
V cover the technologies related to InV networks. The rest of Chapter V and Chapters VI to XII present
the technologies related to V2V and V2I communications which will enable a variety of applications
for safety, trafc efciency, driver assistance and infotainment. Privacy, security, and reliability as key
requirements in deploying VANETs (Vehicular Ad Hoc Networks) are addresses in Chapter XIII. Chapter
XIV discusses simulation architectures, models used for representing the communication among vehicles,
vehicle mobility features, and ways to implement simulation tools with the aim to improve trafc safety
and control. Chapter XV describes in-vehicle network architectures for the next-generation vehicles.
Chapter-wise details are presented bellow.
The introductory chapter presents the emerging area of vehicular networks in the forms of Intra-Ve-
hicle (InV), Vehicle-to-Vehicle (V2V), and Vehicle-to-Infrastructure (V2I) communications. This will
enable a variety of applications for safety, trafc efciency, driver assistance, as well as infotainment, to
be incorporated into modern automotive designs. Critical data is being exchanged within a vehicle and
with outside the vehicle via vehicular networks. Thus, this chapter rst introduces car communications,
potential vehicular applications and wireless technologies, as well as specially designed technologies
DSRC (Dedicated Short Range Communications) standards and communication stack for data exchange.
As the emerging area of vehicular networks is attracting widespread interest from research groups around
the world, this chapter next introduces the consortiums and initiatives working on advanced automotive
technologies in Europe, the United States, Japan, and Singapore. Finally, in the future trend, vehicular
networks still plays a vital role in enhancing the automotive industry for safety, security and entertain-
ment.
Chapter II presents the impact of drive by wire systems on vehicle safety and performance. An
overview of the drive-by-wire technology is presented along with in-depth coverage of salient drive by
systems such as throttle-by-wire, brake-by-wire, and steer-by-wire systems, and hybrid-electric propul-
sion. This is followed by in-depth coverage of technological challenges and the current state-of-the-art
solutions to these technological hurdles. For example, an analytical redundancy/model-based fault-
tolerant control can not only reduce the overall system cost by reducing the total number of redundant

components, but also further improve overall reliability of the system through the usage of a diverse
array of sensory information. Future trends in the drive-by-wire systems include various drive-by-wire
systems in the same vehicle sharing a diversity of sensors and actuators via data fusion methodologies,
integrated control of various drive by wire systems and future communication bus for x-by-wire systems,
for example FlexRay,
Chapter III provides a basic overview of the electromagnetic compatibility (EMC) issues affecting
automotive communications. As the number of electronic systems in automobiles rises, the potential
for electromagnetic interference increases. Designing for electromagnetic compatibility is important to
devote proper attention to electromagnetic compatibility at every stage of an automobile’s development.
Problems discovered late in the design cycle can seriously impact development schedules and product
cost. This chapter provides basic information of electromagnetic compatibility issues affecting automo-
tive communications for non-EMC engineers and engineering managers who work with automotive
networks.
Chapter IV introduces the most widely used automotive networks like LIN (Local Interconnect
Network), CAN (Controller Area Network), MOST (Media-Oriented Systems Transport), and FlexRay.
To fulll the increasing demand of intra-vehicle communications, a new technique based on power
xvii
line communication (PLC) is then proposed. This allows the transmission of both power and messages
without functional barriers. On the other hand, there are several infotainment applications (like mobile
phones, laptop computers) pushing for the adoption of intra-vehicle wireless communications. Thus,
some potential wireless technologies used in the automotive domain, namely Bluetooth, IEEE 802.11
b/g wireless technology – WiFi, and Zigbee are covered here. Finally, the chapter highlights the chal-
lenges of these wired or wireless alternative solutions in automotive networks.
Chapter V elaborates one of the most popular in-vehicle networking technologies called Controller
Area Network (CAN). The chapter begins with an overview of the basis and the general technology of
CAN in automotive industry and the deployment of in-vehicle CAN networks. It then presents the vari-
ous existing and future potential applications that make use of the CAN data, and the related technical
challenges in achieving secure remote monitoring and control of vehicles via CAN. Furthermore, the
chapter elaborates two key components in achieving remote vehicle monitoring and control, namely, the
wireless communication component and data security component. It stresses the importance of secure

data and information ow between vehicles and an application server. Finally, the chapter presents an
overall architecture for secure wireless real-time vehicle monitoring and control environment. In future
rends, the author foresees the area of real-time monitoring and control being a fertile ground for future
automotive innovations and services.
Chapter VI describes the current medium access control (MAC) and routing protocols for vehicular
networks, and the various factors that affect their design and performance. The mobility and speed of the
communicating nodes in vehicular networks add extra dimensions to the challenges faced by the MAC
protocols, in addition to the existing requirements of reliability and efciency. This chapter reviews
some of the existing MAC protocols for vehicular network. For example, basic MAC protocols, the
IEEE 802.11 MAC Extension for Vehicular Networks, and other MAC Protocols for Vehicular Networks
(ADHOC-MAC, the Directional MAC (D-MAC) protocol). Future Intelligent Transportation Systems
require fast and reliable communication between cars (vehicle-to-vehicle) or between a car and a road
side unit (vehicle-to-infrastructure). Ad hoc unicast routing schemes can be divided into two categories:
topology-based routing and position-based routing. Topology-based schemes use a variety of proac-
tive routing schemes (DSDV ((Destination Sequenced Distance Vector routing), Optimized Link State
Routing (OLSR), Fisheye State Routing (FSR)) or reactive approaches (AODV (Ad Hoc On-Demand
Distance Vector Routing), DSR ((Dynamic Source Routing), Temporally Ordered Routing Algorithm
(TORA), Associativity Based Routing Algorithm (ABR), or hierarchical protocols (Cluster Based
Routing Protocol (CBRP), Core Extraction Distributed Ad-hoc Routing (CEDAR) and Zone Routing
Protocol (ZRP)) to create routes.
Popular location services in position-based routing protocols are Distance Routing Effect Algorithm
for Mobility (DREAM) and Grid Location Service (GLS). Context Assisted Routing (CAR) and Spatially
Aware Routing (SAR) are proposed routing algorithms to overcome the problem of topology holes in
position-based routing. Current multicast protocols that can be used in V2V networks include: Posi-
tion-based Multicast (LBM), GeoGRID, Unicast Routing with Area Delivery and Inter-Vehicle Geocast.
Overall, routing of communications for vehicular safety applications remains a challenging topic.
Chapter VII presents a new reactive algorithm based on location information in the context of
vehicular ad-hoc networks. It proposes a Location Routing Algorithm with Cluster-Based Flooding
(LORA-CBF), which is formed with one cluster head, zero or more members in every cluster, and one
or more gateways to communicate with other cluster heads. It rst validates the model at one, two, and

three hops by comparing the results of the test bed with the results of the model developed in OPNET.
For more than three hops, it validates the model by comparing with two non-position-based routing
algorithms (AODV and DSR) and one position-based routing algorithm (GPSR (Greedy Perimeter
xviii
Stateless Routing)). Results show that mobility and network size affects the performance of AODV and
DSR more signicantly than LORA_CBF and GPSR. It is also observed that GPSR and LORA-CBF
behave similarly in terms of the end-to-end delay, and LORA_CBF is more robust in terms of delivery
ratio, routing overhead, route discovery time, and routing load compared with GPSR.
Chapter VIII presents the role of communications in cyber-physical vehicle applications. Cyber-physical
systems use sensing, communications and computing to control the operation of physical devices. The
embedded computers and sensors both within the vehicles and in the infrastructure will be networked
into cyber-physical systems to reduce accidents, improve fuel efciency, increase the capacity of the
transportation infrastructure, and reduce commute time. Communications between nearby vehicles will
enable cooperative control paradigms that reduce accidents more than computing and sensors alone, and
communications between vehicles and the infrastructure will improve the scheduling of trafc signals
and route planning. The chapter describes applications that improve the operation of automobiles, control
trafc lights and distribute the load on roadways. The requirements on the communications protocols
that implement the applications are determined and a new communications paradigm, neighborcast,
is described. Neighborcast communicates between nearby entities, and is particularly well suited to
transportation applications.
Chapter IX incorporates the characteristics of trafc ow into the interference issue at the com-
munication layer of VANETs. There are several fundamental issues, such as connectivity, reachability,
interference and capacity, with respect to information propagation in VANETs. This chapter mainly
addresses the issue of interference, by incorporating the characteristics of trafc into this issue at the
communication layer of VANETs. High node mobility and dynamic trafc features make the interfer-
ence problem in VANETs quite different. As compared with previous efforts to solve this problem
which only considered static network topologies, this work is (to the best of our knowledge), the rst to
demonstrate the interference features in VANETs by incorporating realistic trafc ow characteristics
based on a validated simulation model. Analytical expressions are developed to evaluate the interfer-
ence in VANETs taking account of both the macroscopic and the microscopic trafc ow characteristics.

These analytical expressions are validated within the simulation framework. The results show that the
analytical characterization performs very well to capture the interference in VANETs. The results from
this work can facilitate the development of better algorithms for maximizing throughput in VANETs,
and the research efforts bridging the features of both the communication layer and the transportation
layer will help to build more efcient systems.
Chapter X rst captures the state-of-the-art in the area of trafc control with the assistance of
VANETs in terms of vehicular trafc models, vehicular trafc theories, ow control strategies, and
performance measurement methodologies. It surveys trafc control strategies for optimizing trafc ow
on highways, with a focus on more adaptive and exible strategies facilitated by current advancements
in sensor-enabled cars and VANETs. It provides an overview of new ideas and approaches in the area
of trafc ow control with the assistance of VANETs. This chapter then presents new research into
proactive trafc merging strategies and the potential benets of applying sensor-enabled cars. It shows
how sensor-enabled cars can assist in improving merging algorithms, and compares proactive merg-
ing algorithms against a conventional merging strategy: priority-based merging. Assisted by advanced
sensing and communication technologies, trafc control strategies and merging algorithms will lead
to more efcient use of the current road networks and ultimately help to alleviate trafc congestion. It
has shown that the signicant improvement in trafc ow and the decrease in travel time mainly result
from the decoupling of the merging point and the decision point, and multilane optimizations, such as
pre-lane-changing. Proactive merging strategies can signicantly improve trafc ow by increasing it
by up to 100% and reduce overall travel delay by 30%.
xix
Chapter XI presents the localization problem in cooperative vehicle applications by focusing on the
constraints imposed by the need for precise vehicle localization estimates. Such accurate estimates are
a pre-requisite to deploying vehicles with adequate communications capabilities in real trafc condi-
tions. V2V and V2I safety applications are complex, and the problem does not limit to communications
capabilities. It involves spatial information with respect to the vehicles’ locations relative to each other
and the infrastructure. Thus, V2V and V2I applications are considered as a spatio-temporal problem. The
tenet is that information can be shared only if this is time stamped and related to a spatial description
of the information sources. The chapter formulates the spatio-temporal problem having as constraint
the precision of the pose estimates of the vehicles involved. It formulates the localization problem and

accuracy of digital road maps as a combined issue that needs to be addressed for the successful deploy-
ment of cooperative vehicle applications. The problem formulation is completed by two case studies,
the use of V2V or V2I communications to traverse safely an intersection and an overtaking manoeuvre.
The chapter concludes by including comments and recommendations on the precision limits of the ve-
hicle pose estimations and the potential uncertainties that need to be considered when designing V2V
and V2I applications.
Chapter XII reviews the problem of estimating (in real-time) the position of a vehicle for use in land
navigation systems. After describing the application context and giving a denition of the problem, it
looks at the mathematical framework and technologies involved in the design of positioning systems.
Through a review of some of the various sensor fusion techniques usually encountered in such sys-
tems, it compares the performance of some of the most popular data fusion approaches, and provides
some insights on their limitations and capabilities. The extended Kalman lter (EKF) in data fusion
centralized architectures remains a design of choice for most applications. The chapter then describes
how to make positioning systems more robust and adaptive by detecting and identifying sensor faults.
Finally, it explores possible architectures for collaborative positioning systems, where many vehicles
are interacting and exchanging data to improve their own position estimate using a collaborative and
geometric data fusion approach. One major trend seen in the eld of dense sensor networks is in the use
of multilateration techniques for location accuracy. Despite signicant errors in range estimates between
sensors, multilateration is able to render more accurate location estimates, thus making it suitable for use
in vehicle navigation. With the current evolution of automotive technologies, all vehicles are becoming
networked and equipped with wireless communication capabilities, thus allowing the use of distributed
and collaborative techniques for navigation and positioning. Wireless communications networks are
becoming attractive to localize vehicles using various radio-based range technologies such as received
signal strength indicators (RSSI), power signal attenuation or time-of-arrival (TOA) techniques.
Privacy, security, and reliability as key requirements in deploying VANETs are addressed in Chapter
XIII. Without these strengths, the VANET technology will not be suitable for market diffusion. This
chapter concerns with how to fulll these requirements by using pseudonym-based authentication,
and designing security schemes that do not endanger transport safety while maintaining low overhead.
At the same time, the design improves system usability by allowing nodes to self-generate their own
pseudonyms. It manages security credentials in VANET through self-generation and self-certication

of pseudonyms, which greatly simplies the security management and makes a step towards a usable
system. It employs group signatures to generate certicates which satisfy the requirements of anonymity
and liability attribution, and results show that the computational cost and the overhead are comparable
to the baseline approach. Next, it analyzes the costs imposed by security on the transportation systems
by analyzing data link performance to obtain packet reception probability curves for the pseudonym-
based security systems, and analyzing the impact of safety messaging, security and privacy-enabling
technologies on transportation safety to show that secure communication schemes achieve safety levels
xx
comparable to those with no security at all. This chapter performs a detailed investigation of pseudonym-
based authentication by analyzing several system issues and showing how these security mechanisms
can be applied in practice.
Chapter XIV systematically presents actual issues faced by developers and engineers in the simulation
of VANET applications, some of which are related to the challenges in developing VANET simulators.
It discusses simulation architectures, models used for representing the communication among vehicles,
vehicles mobility features, and simulation tools implementation methods. The focus is on the new trends
in communication protocols and trafc models, and on new facilities incorporated in simulation tools.
Advances in VANET technology and protocols support the adoption and use of more complex mobil-
ity models and of more exible and adaptable trafc controls. VANETs’ rapid topology changes or the
changes in the vehicles mobility as reaction to trafc changes are captured by the simulation models,
which become more or less complicated and include more elements that constrain vehicle mobility: maps,
real trafc conditions (congestion), driver behavior, fuel consumption, pollutant emissions, and so forth.
It also includes a critical analysis of the solutions adopted in some well-known actual simulators. Other
issues related to the use of simulation in the evaluation of applications that aim at improving trafc safety
and control are discussed. Representative city and highway application scenarios are analyzed, and results
obtained by simulation, along with ways these results can be exploited by VANET developers and users,
are highlighted. Future trends in the development of simulators that produce more accurate results, and
their use for the evaluation of more sophisticated trafc control solutions, are also included.
Chapter XV takes a more futuristic look at various types of topologies and protocols that could be
used specically in in-vehicle networks. Varying functionalities of vehicles will require different types
of communication networks and networking protocols. As the size and complexity of the network grows,

integration, maintenance and troubleshooting will become a major challenge. To facilitate integration and
troubleshooting of various nodes and networks, it would be desirable that networks of future vehicles
be partitioned, and the partitions be interconnected by a hierarchical or multi-layer physical network.
These partitions must be appropriately interconnected to handle functional dependencies and for better
diagnostics. A number of network topologies have been presented and analyzed for cost, bandwidth and
message latencies. This chapter describes a number of ways using which the networks of future vehicles
could be designed and implemented in a cost-effective manner. Since future vehicles will also be com-
municating with external entities for various reasons, the chapter also addresses the issues of security,
safety and privacy which should be taken into consideration at the time of designing the in-vehicle net-
work components. Finally, some ideas have been presented in developing simulation models to analyze
various types of networks which will ultimately help in selecting the most appropriate network topology
and various network components for a given set of requirements and specications.
Thus, we have walked through the world of new information and communication technologies be-
ing developed for vehicular systems. We hope that the book is of interest to academia and industry. We
earnestly hope that the insights provided by this book, on the specic information and communication
technologies used in vehicles, will help inspire and spawn a multitude of novel applications and in-
novations.
This book is dedicated to my parents Lanying Guo and Tianfu Guo.
Huaqun Guo
Singapore,October 2008
xxi
Acknowledgment
I would like to extend my utmost gratitude to the people who have, in one way or other, inspired, aided
and contributed to the successful completion of this book.
First of all, I would like to express my sincere gratitude to Deputy Executive Director (Research)
Professor Lye Kin Mun at the Institute for Infocomm Research (I
2
R) for his strong encouragement of
my editing works.
I would also like to thank the A*CAR (A*STAR Capabilities for Automotive Research) taskforce,

and the management of Institute for Infocomm Research (I
2
R) for providing me the opportunity to carry
out research into the exciting area of vehicular networks. In particular, I would like to thank Dr. Feng
Bao and Dr. Yongdong Wu at I
2
R for their support.
Special thanks to all reviewers for their expertise, time, effort and timely response throughout the
peer evaluation process. In particular, I wish to express my appreciation to the members of the Editorial
Advisory Board for their guidance, support and constant encouragement.
I would also like to take this opportunity to thank Tyler Heath and Heather A. Probst for their as-
sistance with this book.
Last but not least, the heartiest gratitude is given to my family for their love and encouragement.
Huaqun Guo
Institute for Infocomm Research, A*STAR, Singapore

1
Copyright © 2009, IGI Global, distributing in print or electronic forms without written permission of IGI Global is prohibited.
Chapter I
Introduction:
An Emerging Area of Vehicular Networks
and Data Exchange
Huaqun Guo
Institute for Infocomm Research, A*STAR, Singapore
INTRODUCTION
In recent years, control systems of automobiles
have moved from the analog to the digital do-
main. In particular, x-by-wire systems are ap-
pearing and have driven research efforts of the
whole automotive industry for the recent decade.

Networked Electronic Control Units (ECUs) are
increasingly being deployed in automobiles to
realize diverse functions such as engine manage-
ment, air-bag deployment, and even in intelligent
brake systems. For example, at least 70 networked
ECUs are employed in a Mercedes S-Class car
(Heffernan & Leen, 2008; Vasilash, 2005). At the
same time, emerging vehicular networks in the
forms of Intra-Vehicle (InV), Vehicle-to-Vehicle
ABSTRACT
Emerging vehicular networks in the forms of Intra-Vehicle (InV), Vehicle-to-Vehicle (V2V), and Vehicle-
to-Infrastructure (V2I) communications will enable a variety of applications for safety, trafc efciency,
driver assistance, as well as infotainment to be incorporated into modern automobile designs. At the
same time, networked Electronic Control Units (ECUs) are increasingly being deployed in automobiles to
realize functions such as engine management, air-bag deployment, and even in intelligent brake systems.
In addition, users now expect to sit in an automobile and have their brought-in devices, and beamed-in
services harmoniously integrated with the built-in interfaces inside the automobile. Thus, widespread
adoption of vehicular networks is fast becoming a reality and critical data is being exchanged with-inside
and with-outside vehicle via vehicular networks. This chapter gives an overview of this emerging area
of vehicular networks, its potential applications, its potential wireless technologies for data exchange,
and its research activities in the Europe, the United States (U.S.), Japan, and Singapore.
2
Introduction
(V2V), and Vehicle-to-Infrastructure (V2I) com-
munications are fast becoming a reality and will
enable a variety of applications for safety, trafc
efciency, driver assistance, as well as infotain-
ment to be incorporated into modern automobile
designs.
There are currently a number of study groups

working on car communications and den-
ing the standards for various applications. InV
Communications, such as CAN (Controller Area
Network, 2008; CiA, 2008), LIN (Local Inter-
connect Network, 2008), FlexRay (2008), are
used for interconnecting in-car ECUs, sensors,
and so on. V2V Communications, such as IEEE
802.11p (IEEE 802.11p, 2008; Jiang & Delgrossi,
2008), Dedicated Short Range Communications
(DSRC) (Dedicated Short Range Communica-
tions, 2008), may be used for safety applications.
V2I communications, e.g. IEEE 802.11p and IEEE
1609 Family of Standards for Wireless Access in
Vehicular Environments (WAVE, 2008) may be
used for trafc information.
In addition, users now expect to sit in an au-
tomobile and have their brought-in devices and
beamed-in services harmoniously integrated with
the built-in interfaces inside the automobile. To
integrate mobile phones and digital music players,
Ford designs Ford Sync that integrates voice-ac-
tivated in-car communication and entertainment
system (Ford Sync, 2008). RM MICHAELIDES
provides wireless CAN interfaces to transmit
CAN between different networks using Bluetooth,
RFID (radio-frequency identication), Infrared,
UHF (ultra high frequency), etc (Michaelides,
2008). A Controller Area Network Gateway to
ZigBee was described in (Kuban, 2007). There
are some wireless CAN products, such as CANRF

(Dammeyer, 2008) and CAN Bridge (Matric,
2008). The performance of wireless CAN in terms
of latency and throughput was studied in (Dridi,
Gouissem, Hasnaoui, & Rezig, 2006).
Thus, with vehicular networks fast becoming
commonplace, critical data is being exchanged
with-inside and with-outside vehicle via vehicu-
lar networks, and new technologies have been
developed for vehicular networks. This chapter is
meant to introduce the emerging area of vehicular
networks and data exchange, give an overview of
the new technologies for car communications,
and present automotive research activities in the
Europe, the United States (the U.S.), and Japan
as well as in Singapore.
CAR COMMUNICATIONS
New technologies are being developed for ve-
hicular networks and these networks provide an
efcient method for today’s complex car com-
munications. Figure 1 shows the example of InV,
V2V and V2I communications.
InV provides communication among ECUs/
sensors in a vehicle while V2V and V2I provide
communications among nearby vehicles and be-
tween vehicles and nearby xed roadside equip-
ments. Vehicular networks are a cornerstone of
the envisioned Intelligent Transportation Systems
(ITS). By enabling vehicles to communicate with
its function systems via InV communication,
with other vehicles via V2V communication as

well as with roadside base stations via V2I com-
munication, vehicular networks will contribute
to safer and more efcient roads by providing
timely information to drivers and concerned
authorities.
Potential Applications
The emerging vehicular networks will enable a
variety of applications for safety, trafc efciency,
driver assistance and infotainment:
1
. Safety
: Vehicular network technologies will
be applied to reduce accidents so as to save
lives and reduce injuries. Examples of such
applications include vehicle breakdown and
obstacle detection, lane departure warn-
ing, accident warnings, collision warning,