Tutorials to be presented at VTC 2006 Fall
All tutorials will take place on Monday 25th September
T-BWA: Broadband Wireless Access - The Next Wireless Revolution
Presenter: Benny Bing, Georgia Institute of Technology
Time: AM
Room: Picardie A
Abstract
Broadband wireless access is the third wireless revolution, after cellphones (1990s) and Wi-Fi (2000s). It is viewed by many carriers and cable operators as a “disruptive” technology and rightly so. The broadcast nature of wireless transmission offers ubiquity and immediate access for both fixed and mobile users, clearly a vital element of next-generation quadruple play (i.e., voice, video, data, and mobility) services. Unlike wired access (copper, coax, fiber), a large portion of the deployment costs is incurred only when a subscriber signs up for service. An increasing number of municipal governments around the world are financing the deployment of multihop wireless networks with the overall aim of providing ubiquitous Internet access and enhanced public services.
Tutorial outline
This tutorial will provide a comparative assessment of the key issues and technologies underpinning promising broadband wireless access solutions such as 802.16 (Wi-Max), long-range/multihop 802.11 (Wi-Fi), wireless DOCSIS, 3G/4G, mobile TV, digital TV broadcast, 802.20 (mobile broadband), 802.21 (media independent handoff and interoperability), and the emerging 802.22 (wireless regional area networks) standard. Key topics include licensed and unlicensed spectrum consideration; reliable physical layer transmission using multiple antennas; multichannel medium access protocols with QoS provisioning; wireless access topologies: point-to¬point, point-to-multipoint, peer-to-peer multihop (mesh); wireless multimedia services: wireless IP-TV, wireless VoIP; mobility; cognitive radio technologies; advanced wireless security; wireless/wireline integration.
Primary Audience
The tutorial is for anyone who wish to study the underlying principles of emerging broadband wireless access technologies. Whether you are an entrepreneur, a CTO, a business executive or a scientist, you will discover that the thought-provoking material provided by the tutorial not only help you master the subject but also serve as a rich source of interesting ideas.
Novelty
This is the first tutorial that provides a comparative assessment of emerging broadband wireless technologies.
Biography
Benny Bing is an associate director of the Georgia Tech Broadband Institute. He has published over 40 papers, 10 books, and 1 book chapter. His publications have also appeared in the IEEE Spectrum. His books on wireless networks are highly regarded by many technology visionaries. They contain forewords from both chairmen of the IEEE 802.11 Working Group since its inception, the inventor of Internet technology, and the inventor of the first wireless protocol. In early 2000, his groundbreaking book on wireless LANs was adopted by Cisco Systems to launch the Cisco-Aironet Wi-Fi product. The product has since enjoyed phenomenal success, dominating the corporate arena and capturing over 60% of the Wi-Fi market share. He was subsequently invited by Qualcomm Inc. in San Diego, CA to conduct a customized course on wireless LANs for its engineering executives. He was again invited to conduct a similar course for the Office of Information Technology. In 2002, his edited book on wireless LANs was extensively reviewed by the IEEE Communications Magazine, IEEE Network, and ACM Networker, the first time a book has been reviewed by all three journals. He is currently an editor for the IEEE Wireless Communications Magazine, and has also guest edited for the IEEE Communications Magazine and the IEEE Journal on Selected Areas on Communications. In addition, he was featured in the MIT Technology Review in a special issue on wired and wireless technologies as well as the Atlanta Business Chronicle and the IEEE Spectrum. He has served on the wireless networking panel for National Science Foundation (NSF) and was selected as one of the 10 best wireless designers in the United States by Building Industry Consulting Services International (BICSI), a 22,000-industry member telecommunication association based in Tampa, Florida. He was invited by NSF to participate in an NSF-sponsored workshop on “Residential Broadband Revisited: Research Challenges in Residential Networks, Broadband Access and Applications”, held on October 2003. He is also a frequent tutorial presenter at several IEEE Communications Society flagship conferences such as IEEE Infocom and IEEE Globecom. He is a recipient of the Lockheed-Martin Fellowship and a best paper award at the 1998 IEEE International Conference on ATM. He is a Senior Member of IEEE and has over 100 international research citations to his name. His current research interests include broadband access, wireless LANs, cognitive radio, and queueing theory.
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T-CMS: Coding for MIMO Systems
Presenters: Tolga Duman, Arizona State University, and Ali Ghrayeb, Concordia University
Time: AM
Room: Picardie B
Abstract
Achieving reliable high-speed data transmission over wireless links is a challenging task due to multipath fading and interference from other users. The single most effective technique to combat such adverse effects is to introduce diversity into the system. There are many different diversity techniques including temporal, frequency, and spatial diversity. Furthermore, different diversity techniques may be combined to enhance the performance of the wireless system. Space-time coding, a new coding paradigm suitable for multiple antenna systems, is a successful example that combines temporal diversity (through channel coding) and spatial diversity (through multiple transmit and receive antennas). This tutorial gives a complete overview of the various emerging space-time coding techniques. These include space-time trellis codes, space-time block codes, turbo codes, and concatenated codes with iterative decoding, among others. The tutorial focuses on the construction and performance analysis of such coding schemes over various wireless channels. In addition, it addresses information theoretical limits for multi antenna systems over wireless channels. Participants will also see comparisons between these coding schemes in terms of performance and complexity. In addition, several practical space-time coding architectures such as BLAST and its variants will be described. Other practical issues such as antenna selection at the transmitter and/or receiver and the effects of sub-channel correlation on the system performance will also be considered.
Tutorial outline
• Channel capacity/Information rates for MIMO wireless systems
- Shannon capacity for MIMO systems over ergodic flat fading channels
- Outage capacity for MIMO systems over non-ergodic flat fading channels
- Information rates under signaling constraints for MIMO over flat fading channels
- Capacity and Information rates for frequency selective fading
• Alamouti scheme / space-time block codes
- 2-transmit diversity, Alamouti scheme
- Decoding and performance analysis
- Extensions to space-time block codes
• Space-time trellis codes
- Code design principles over quasi-static fading channels
- Decoding of space-time trellis codes
- Performance analysis / bounds
- Performance comparisons with space-time block codes and channel capacity
• High rate low complexity space-time coding
- D-BLAST
- V-BLAST
- Other approaches
• Concatenated coding and iterative decoding for MIMO systems
- Turbo coded modulation for multiple antenna systems
- Serial concatenation for MIMO systems
- Coding for MIMO over frequency selective fading channels
- Iterative equalization/decoding
• Practical considerations
- Large number of antennas
- CSI estimation
- effects of sub-channel correlation
• Non-coherent space-time coding
- Differential approaches
- Unitary space-time codes
- Turbo and Trellis coding with unitary space-time constellations
• MIMO OFDM systems
- Overview
• Antenna selection at the transmitter and the receiver
- Selection based on channel capacity / Simplified algorithms
- Selection based on received signal to noise ratio
- Effects of antenna selection on achievable diversity order
- Space-time code design with antenna selection
Primary Audience
Students, researchers and industry affiliations, and individuals working for government, military, science and technology institutions who would like to learn more about error control coding for multiple antenna communication systems.
The tutorial is intended to provide the audience with a complete overview of the various emerging coding techniques for multiple antenna systems, including space-time codes, turbo codes, and concatenated coding with iterative decoding, among others. In addition, the tutorial will cover the latest findings in this field.
Novelty
We will be presenting an in depth coverage of MIMO systems, we do not intend to give novel results, but instead cover (recent) important topics in MIMO systems.
Biographies
Tolga M. Duman received the B.S. degree from Bilkent University in 1993, M.S. and Ph.D. degrees from Northeastern University, Boston, in 1995 and 1998, respectively, all in electrical engineering. In August 1998, he joined the Electrical Engineering faculty of Arizona State University where he is currently an associate professor. Dr. Duman's current research interests are in digital communications, wireless and mobile communications, channel coding, turbo codes, coding for recording channels, and coding for wireless communications. Dr. Duman published about 30 journal papers and 60 refereed conference papers in these areas. He is a recipient of the National Science Foundation CAREER Award, IEEE Third Millennium medal, and IEEE Benelux Joint Chapter best paper award (1999). He is a member of the IEEE Information Theory and Communication Societies. He co-instructed technical tutorials on coding for MIMO systems at IEEE Globecom 2003 and IEEE WCNC 2004 and IEEE ICC 2005.
Ali Ghrayeb received the Ph.D. degree in electrical engineering from the University of Arizona, Tucson, AZ, in May 2000. From 2000 to 2002, he was an Assistant Professor in the Electrical Engineering Department at the American University of Sharjah, UAE. Since August 2002, he has been with the Department of Electrical and Computer Engineering, Concordia University, Montreal, Canada, where he is an Asscociate Professor. His research interests include digital and wireless communications, channel coding, turbo codes, space-time codes, linear and nonlinear equalization, and coding for data transmission and storage. He has published over 50 refereed technical papers in the above research areas. He served/is serivg on the Technical Program Committee of several IEEE conferences, including VTC 2003/2004, ICC 2004/2004, and PIMRC 2003/2004. He co-instructed technical tutorials on coding for MIMO systems at IEEE Globecom 2003, IEEE WCNC 2004, and IEEE ICC 2005.
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T-ISE:
Introduction to OFDM and MIMO communication systems with emphasis on DVB-H, 802.11n and 802.16e
Presenters: Raghu Mysore Rao, XILINX INC., and Ahmed M. Eltawil, The Henry Samueli School of Engineering
Time: AM
Room: Auteuil
Abstract
High data rate applications are driving the need for high throughput and spectrally efficient broadband communication systems. Efficient modulation schemes and multiple antenna techniques are being explored for such applications. MIMO-OFDM is one such promising technology. OFDM modulation has been adopted by almost all the major broadband wireless standards such as, 802.11a/g, DVB-T/DVB-H, 802.16, UWB, etc. MIMO-OFDM is also finding its way into some of the newer standards such as 802.11n, 802.16 and 802.16e. The key aspects of all of these standards are reliability, high-throughput and mobility.
In this tutorial we will start off by discussing the wireless propagation environment and study the characteristics of the wireless environment in the presence of scattering and mobility. We will introduce the audience to the key concepts of OFDM and MIMO-OFDM systems, relating aspects of information theory that led to the development of MIMO-OFDM systems. We will then consider the practical issues related to OFDM system and receiver algorithms, including the impact of RF and analog impairments on OFDM and MIMO-OFDM systems. We will explain why state of the art standards are converging on OFDM and MIMO as choice technologies. DVB-H will be used as a showcase of OFDM technology while 802.11n and 802.16 will be used to exemplify MIMO-OFDM technology. We will discuss the physical layer of these standards as well as their key performance metrics.
In addition we will discuss some architectural aspects of wireless systems and the tradeoffs of implementing them on ASICS and FPGAs. FPGAs are a popular platform for developing communication systems at the basestation, given their configurability and time to market advantage. Newer generation FPGAs also have dedicated fabric for efficient implementation of DSP and communication systems. Newer, higher level design methodologies, further improve this time to market advantage of FPGAs. We will briefly discuss these methodologies and also introduce some of the DSP and communication centric features of popular FPGAs.
Tutorial Outline
1. Introduction to wireless propagation environment
a. Free space path loss, scattering, multipaths, etc.
b. Flat fading and frequency selective channels
c. Various forms of diversity; time, frequency and spatial diversity
d. Coherence bandwidth, Coherence time, delay spread, Doppler spread
e. MIMO channel characteristics
2. Introduction to OFDM
a. Principles of OFDM modulation
b. OFDM transmitter, Cyclic prefix and postfix
c. Interleaving and Bit Interleaved Coded Modulation
d. OFDM systems, continuous and packet mode systems
e. OFDM receiver principlesi. Packet detection
ii. Block boundary detection(Timing acquisition)
iii. Channel estimation and equalization
iv. Carrier frequency offset estimation
v. Sampling frequency offset estimation
3. Introduction to MIMO
a. MIMO Capacity
b. STBC, SM, Feedback MIMO systems
c. MIMO receivers, ZF, MMSE, SIC, etc
4. Introduction to MIMO-OFDM
5. RF impairments
a. I/Q mismatch and its impact on MIMO-OFDM systems
b. Phase noise and its impact on MIMO-OFDM systems
6. OFDM and MIMO-OFDM Wireless communication systems
a. DVB-T/DVB-H and variants such as ISDB-T (Japan) and T-DMB (Korea)
b. 802.11a/n
c. 802.16/802.16e
7. Communications system design
a. Architecture selection for communication systems (FPGAs/ASICs)
b. Features of present day FPGAs for DSP and Comm. Systems design
c. Next generation design methodologies
8. Summary
Primary Audience
Wireless communication professionals and executives who are interested in understanding OFDM, MIMOOFDM systems as well as those looking for an introduction to DVB-H, 802.11n and 802.16e.
Novelty
MIMO and OFDM are two of the hottest topics in wireless communications today. There is significant interest in the industry towards an understanding of 802.11n, 802.16e and DVB-H systems.
Biographies
Dr. Raghu Rao is a Senior Staff communications Systems Engineer in the Advanced Systems Technology Group at Xilinx Inc. He has a PhD in wireless communications from UCLA where his thesis topic was Performance Analysis of MIMO-OFDM Systems. Prior to joining Xilinx Raghu worked for Texas Instruments, Logic Modeling Corporation and was the Director of Engineering at Exemplar Logic. Most recently Raghu was the VP of engineering for a communications start-up developing MIMO-OFDM and DVB-H technologies. From 19992004 he was a fulltime PhD candidate researching algorithms for MIMO-OFDM wireless communication systems. From 1989-1992 he was at Texas Instruments (India) Pvt. Ltd. where he worked on placement and routing algorithms for ASICs and FPGAs. Between 1992 and 1994 he was involved in developing software for hardware modelers at Logic Modeling Corp. From 1994-1999 he was at Exemplar Logic Inc. where he worked on timing analysis and timing optimization algorithms for FPGA designs and later on was Director of Engineering where he was responsible for all of Exemplar Logic’s engineering activities. His interests are in digital communication algorithms, signal processing and efficient DSP and communication algorithms for FPGAs.
Ahmed Eltawil is an assistant professor with the Electrical Engineering and Computer Science Dept. at the University of California, Irvine. He received his doctorate degree from the University of California, Los Angeles in 2003 with a focus on VLSI architectures for wideband wireless communications. From January 2001 till August 2003 he was director of ASIC Engineering at Innovics Wireless, a fabless semiconductor company, where he lead the development of the first reported diversity enabled third generation W-CDMA mobile station. Currently at UCI, his research interests are in advanced digital circuit and signal processing techniques for communication systems, including both circuit and system design. Dr Eltawil holds several awards in his field including being the first Henry Samueli chair of Engineering at the University of California.
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T-LTE:
3G Long Term Evolution (LTE)
Presenter: Farooq Khan, Samsung Telecommunications America
Time: AM
Room: Argenteuil
Abstract
An extensive effort is underway in 3G Partnership Project (3GPP) to develop a framework for the evolution of the 3G radio-access technology towards a high-data-rate, low-latency and packet-optimized radio access technology. A number of advanced technologies such as low-PAPR orthogonal uplink multiple access based on SC-FDMA, inter-cell interference mitigation techniques, MIMO multi-antenna technologies, low-latency channel structure and singe-frequency network (SFN) broadcast etc, are being considered for the radio-interface long term evolution (LTE) beyond HSPA (High Speed Packet Access). In this tutorial, we provide an overview of the key radio-interface technologies for LTE along with their impact on system performance improvements. We will also discuss the LTE system architecture and standard development schedule briefly.
Tutorial outline
1. Overview of LTE System Requirements
2. Uplink multiple Access
a. Basic principles of Single Carrier FDMA (SC-FDMA)
b. PAPR reduction techniques for SC-FDMA
c. Uplink channel structure
3. Downlink Multiple Access
a. OFDMA Overview
b. Frequency diversity and frequency-selective multi-user scheduling
c. Downlink channel structure
4. Link Adaptation and Hybrid ARQ
a. Frequency-domain link adaptation in OFDMA/SC-FDMA
b. Synchronous vs. Asynchronous and Non-adaptive vs. Adaptive Hybrid ARQ
c. Chase combining vs. Incremental Redundancy (IR)
5. Inter-cell interference mitigation techniques
a. Inter-cell-interference randomization
b. Inter-cell-interference cancellation
c. Inter-cell-interference co-ordination/avoidance
6. Enhanced Multimedia Broadcast and Multicast Service (E-MBMS)
a. Single-Frequency Network (SFN) operation
b. Layered QoS (Quality of Service)
c. E-MBMS channel structure
7. MIMO Techniques
a. Single-user vs. Multi-user MIMO considerations
b. Transmit diversity and beamforming
c. Rank Adaptation
d. MIMO for multicasting/broadcasting
8. Flexible bandwidth support
a. Synchronization and cell search
b. Mobile receiver capabilities
c. Implications on system design
9. LTE Architecture
10. LTE Standard Development Schedule
Primary Audience
Research engineers from industry and academia, wireless system designers and managers.
Novelty
A first tutorial on LTE to the best of author’s knowledge.
Previous Tutorial Experience
Offered highly attended tutorials on the topic of “TCP/IP over Wireless Networks” at VTC-2000 Spring and VTC-2000 Fall conferences.
Biography of Speaker
Farooq Khan is Technology Director in Wireless Solutions Lab. at Samsung in Dallas, Texas. His responsibilities include design, performance evaluation and standardization of next generation wireless communications systems with current emphasis on the 3G long term evolution (LTE). Previously, he was Member of Technical Staff at Bell Laboratories - Lucent Technologies, New Jersey, where he conducted research on evolution of cdma2000 and UMTS systems towards high speed packet access (HSPA). Before joining Bell Laboratories, he was Research Engineer with Ericsson Research in Stockholm Sweden, where he contributed to the design and performance evaluation of EDGE and WCDMA technologies. He has published over 30 refereed conference and Journal papers and has 12 patents issued, all in the area of wireless communications, MIMO and communication theory. He holds an M.S. degree in electrical engineering from Ecole Supérieure d’Electricité, Paris, France and a Ph.D. degree in computer science from Université de Versailles, France.
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T-IMS:
IP Multimedia Subsystem (IMS): A Platform for Fixed-Mobile Convergence and Next Generation Network Services
Presenter: Vijay K. Varma, Telcordia
Time: PM
Room: Picardie A
Abstract:
The IP Multimedia Subsystem (IMS) is considered as the platform of choice for providing a unified session control on top of various access network technologies for realizing flexible multimedia applications. IMS, with its access-agnostic session layer, is also driving the concept of Fixed-Mobile Convergence by merging the fixed and mobile telecommunication networks with the Internet and the adoption of IP technologies within the telecom domain. IMS represents conceptually a combination of the traditional fixed and mobile networks from the telecom domain with emerging VoIP and Internet applications in order to implement a seamless multimedia service environment. This tutorial will address IMS vision, evolution from GSM/UMTS, IMS concepts, procedures, protocols and services. The tutorial will also cover fixed-mobile convergence, migration scenarios, interworking with existing networks, standardization activities, and early deployments of IMS networks.
Tutorial outline
Introduction
- IMS vision
- Evolution from GSM/UMTS
IMS principles and concepts
- Architecture requirements
- IMS architecture overview (including network elements and their functions)
- IMS Reference points
- IMS identities
IMS Procedures
- Authentication
- Registration, re-registration, deregistration
- Session initiation, termination, release
- Interworking with PSTN
- IMS session examples
IMS Security
- Security threats
- IMS security model
- Authentication and key agreement
- Security domains
IMS Protocols
- Session Initiation Protocol (SIP)
- Session Description Protocol (SDP)
- Real Time Protocol (RTP)
- Diameter
- H.248
Fixed-Mobile Convergence
- Mobile network evolution
- All-IP network concept
- TISPAN NGN
- Convergence
IMS Services
- Voice
- Presence
- Instant messaging
- Push-To-Talk
- Conferencing
IMS standardization
- 3GPP Release 7
- 3GPP2 MMD
- Voice Call Continuity (VCC)
- Future directions
IMS in real world
- Field trails
- Early deployments
Summary
Primary Audience
Practicing engineers, research scientists, and mid-level managers in telecom and Internet sector (wired and wireless, vendors, service providers and application developers), engineers and scientists involved in standards activities.
Novelty
IMS is a “buzzword” in telecommunications. This tutorial will provide a reality check by offering a concise view of concepts, principles, applications, services, and real-world experiences.
Biography of Speaker
Vijay K. Varma is a Senior Scientist in the Wireless Systems Research Department of Telcordia, Red Bank, NJ. He has 20 years experience in wireless communications and has been involved in various systems issues, including speech coding, signaling and call control protocols, wireless data, mobility management protocols, and wireless network architectures. His current research interest includes 3G/WLAN interworking, IP Multimedia Subsystems (IMS) enhancements, wireless system architecture evolution (SAE), location-based services (LCS), and wireless security. He has published several papers in the area of wireless communications and has given many tutorials, organized workshops and sessions at various IEEE conferences. He attends 3GPP standards meetings relating to IMS, SAE, and LCS.
Dr. Varma received the M.Tech degree from the Indian Institute of Technology, Kanpur, and the Ph. D. degree from Southern Methodist University, Dallas, TX, both in Electrical Engineering. He is a Senior Member of the IEEE. He received the Frederick E. Terman award from the School of Engineering and Applied Science, Southern Methodist University.
Prior IEEE Conference Experience
- Technical Program Vice Chair – IEEE WCNC 2005 (in charge of Technology and Business Applications Panels), March 2005.
- Panel chair at IEEE VTC 2004 “Enabling Heterogeneous Wireless Networking: Technologies and Challenges Ahead”, Milan, May 2004.
- Organized and presented a ½ day tutorial at IEEE ICC 2003 on “Evolution of UMTS Core Networks: 3G and Beyond” (with D. Wong)
- Organized and presented a ½ day tutorial at IEEE Globecom 2002 on “Evolution of Core Networks from GSM to UMTS and Beyond”
- Organized and presented a ½ day tutorial at IEEE WCNC 2002 on “Evolution of Core Networks from GSM to UMTS and Beyond”
- Organized and presented a full-day tutorial at IEEE Globecom 2001 on” Evolution of Core Networks from GSM to UMTS” (with D. Wong)
- Organized and presented a ½ day tutorial at IEEE PIMRC 1997 on “Wireless Technologies and the National Information Infrastructure”
- Organized and presented a full-day tutorial at International Superhighway Summit (ISS), Singapore, 1996 on “The Role of Wireless Technologies on the Information Superhighway”
- Organized and presented a full-day tutorial at IEEE ICC 1994 on “Speech Coding for Wireless Communications”
- Member of the organizing committee, IEEE Networks for Personal Communications (NPC ‘94), 1994.
- Member of TPC for a number of IEEE conferences
Other relevant experience
- Associate Editor, IEEE Vehicular Technology Magazine, Mobile Networks
- Associate editor, “Special Issue on IMS as Next Generation Network Service Delivery Platform: Architecture, Protocols, and Applications,” IEEE Vehicular Technology Magazine, Planned for early 2007.
- Lead guest editor “Integration of 3G Wireless and Wireless LANs”, IEEE Communications Magazine, November 2003.
- Guest editor “Advances of Wireless LANs and PANs”, Kluwer Wireless Personal Communications Journal, July 2005.
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T-DGP:
Design Guidelines for Network Layer Protocols in Ad Hoc and Sensor Networks
Presenter: Ivan Stojmenovic, University of Ottawa
Time: PM
Room: Picardie B
Abstract
This tutorial concentrates on the network layer of ad hoc networks, with various assumptions about physical and medium access layer protocols. Despite huge number of publications, good understanding of limitations of ad hoc and sensor networks, and existence of simulators with physical layer details, the proposed solutions rarely consider real limitations and realistic physical layer as part of protocol. This tutorial will address these issues. The network layer problems can be divided into two groups: data communication, and topology control problems. In data communication problems, such as routing, quality-of-service routing, geocasting, multicasting, and broadcasting, the primary goal is to fulfil a given communication task successfully between nodes in ad hoc network. The secondary task is to minimize the communication overhead (since bandwidth in wireless communication is typically limited) and power consumption by battery operated nodes. Location updates for efficient routing are also covered. Topology control problems include neighbour discovery, determining transmission radii (fixed or adjustable), connectivity issues, partitioning for data replication, activity scheduling, Bluetooth scatternet formation problem (connected degree limited structure with nodes taking master and/or slave roles), finding a sparse connected structure (resembling minimal spanning trees), and finding connected dense planar structure.
This tutorial will also review ongoing research on the ‘hot’ topic of sensor networks, including problems such as: physical properties, sensor training, medium access, sensor area coverage, object location, sensor position determination, routing, connectivity, data dissemination and gathering, data centric operations, and transport layer. The main paradigm shift is to apply localized (or greedy) schemes as opposed to existing protocols requiring global information. Localized algorithms are distributed algorithms where simple local node behaviour achieves a desired global objective. Localized protocols provide scalable solutions, that is, solutions for wireless networks with an arbitrary number of nodes, which is the main goal of this plan. Sensor and rooftop/mesh networks, for instance, have hundreds or thousands of nodes. It is recognized that scalability for routing and for sensor networks operations is only possible with the position information, which becomes available with increasing number of affordable software and hardware solutions. For some other tasks, e.g. broadcasting, position information helps but scalable solutions without it are also possible.
Tutorial outline
Introduction- taxonomy
Routing with unit graphs
Routing with realistic physical layer
Broadcasting in ad hoc networks
Sensor networks
Sensor area coverage
Primary Audience
Ad hoc and sensor networks are currently hot topic with rapidly increasing research and commercial interest (new conferences, journals emerged in the area), and network layer is at the center of research activities. The tutorial should attract researchers, graduate and even companies that want to design protocols for real sensor networks.
Novelty
The main objective of the tutorial is to present state of the art research results on topology control, formation, power management, routing and broadcasting in ad hoc networks, with emphasizes on localized and position based techniques. Physical layer impact on the design of network layer protocols is also discussed. Most of presented techniques are based on localized geometric and graph structures.
Ad hoc and sensor wireless networks are normally modeled as unit disk graphs. In a unit disk graph, message sent by any node reaches simultaneously all its neighbors whose distance to the transmitting node is no more than the transmission radius, which is equal for all nodes. In sensor networks, the model is extended to consider sensing radius in addition to transmission radius. In all cases, however, for each particular node, the assumption made is that transmission is received if and only if the distance between transmitter and receiver is up to certain threshold transmission radius R. However, recent studies, considering lognormal shadowing model at physical layer, reported a major failure of existing popular routing protocols, considered even now for becoming standards, when realistic physical layers are considered. We anticipate a major paradigm shift in overall research on ad hoc network protocol design, by considering more realistic physical layers, such as lognormal shadowing model at the beginning, Raleigh fading and other models later on. In this tutorial, we present guidelines on how to design network layer protocols when the unit disk graph model is replaced with a more realistic physical layer model. Instead of merely using the transmission radius in the unit disk graph model, physical, MAC and network layers share the information about a bit and/or packet reception probability as a function of distance between nodes.
Biograph
Ivan Stojmenovic received Ph.D. degree in mathematics in 1985. He earned a third degree prize at International Mathematics Olympiad for high school students in 1976. He held regular or visiting positions in Serbia (Institute of Mathematics, University of Novi Sad, 1980-1987), Japan (Electrotechnical Laboratory, Tsukuba, 1985/6), USA (Washington State University, Pullman, WA, and University of Miami, FL, 1987/88), Canada (Univ. of Ottawa, since 1988), France (Amiens 1998, Lille 2002-2005) and Mexico (DISCA, IIMAS, Universidad Nacional Autonoma de Mexico, 2000/02). He is currently Full professor of computer science at the School of Information Technology and Engineering, University of Ottawa.
He published >200 different papers in referred journals and conferences; >80 of them are in journals with ISI impact factor, >20 are in IEEE or ACM journals. He edited two books with Wiley: ‘Handbook of SensorNetworks: Algorithms and Architectures’(2005) and ‘Handbook of Wireless Networks and Mobile Computing’ (2002), and co-edited ‘Mobile Ad Hoc Networking’ (IEEE Press, 2004). His most significant publications can be seen at www.site.uottawa.ca/~ivan. He co-authored over 30 book chapters; half of them are being published since 2005. He collaborated with >80 co-authors with Ph.D. and a number of their graduate students from >20 different countries. He (co)supervised over 30 Ph.D. and master theses, and published over 120 joint articles with supervised students. His current research interests are mainly in wireless ad hoc, sensor and cellular networks. His research interests also include parallel computing, multiple-valued logic, evolutionary computing, neural networks, combinatorial algorithms, computational geometry, graph theory, computational chemistry, image processing, programming languages, and computer science education. He was cited >2200 times and is in the top 0.58% most cited authors in Computer Science (Citeseer August 2005). One of his articles, on broadcasting in ad hoc wireless networks, was recognized as Fast Breaking Paper, for October 2003 (as theonly one for the entire computer science), by Thomson ISI Essential Science Indicators http://esitopics.com/fbp/fbp-october2003.html. His received: Best Paper Award, at the IFIP PWC, 2004; Faculty of Engineering’s 2004-2005 George S. Glinski Award for Excellence in Research, University of Ottawa; NSERC Collaborative Research Development (CRD) project for February 2005- February 2008, as Principal Investigator.
He presented several tutorials on ad hoc and sensor networks, and gave a number of invited talks. He was Director of Ottawa-Carleton Institute for Computer Science (2002-2004) and wrote an article ‘Advice for writing theses and papers’ (on his web site www.site.uottawa.ca/~ivan), containing guidelines for writing and publishing research results.
He is currently a managing editor of Journal of Multiple-Valued Logic and Soft Computing (received Certificate of Appreciation from IEEE Computer Society in 2002 for establishing and maintaining the journal), International Journal of Parallel, Emergent and Distributed Systems (IJPEDS; T& F), and Ad Hoc & Sensor Networks, An International Journal (AHSWN), and editor of several journals including IEEE Transactions on Parallel and Distributed Systems, Parallel Processing Letters, Int. J. High Performance Computing and Networking (IJHPCN), Int. J. Wireless and Mobile Computing (IJWMC), Int. J. of Sensor Networks (IJSN) and Int. J. Distributed Sensor Networks (IJDSN).
He guest edited recently special issues in several journals including IEEE Computer Magazine, IEEE Networks, IEEE Transactions on Parallel and Distributed Systems, Wireless Communications and Mobile Computing, Ad Hoc Networks, Telecommunication Systems, Cluster Computing, Int. J. Found. Computer Science.
He chaired (and handled submissions for) 20 workshops and conferences (7 in 2005). He was organizer, chair or advisor for 8 conferences. In 2005, he served as member of 38 program committees (and already 28 for 2006). Among others, he was program vice-chair at IEEE MASS and IEEE WONS, workshop co-chair at IEEE ICDCS in 2003-2005; IEEE ICDCS 2003; HICSS, 2000, 2002, 2003; ICPDS, Taiwan, 2002; ICPP, Toronto, 2000; and is/was program committee member at ACM Mobihoc 2006, ACM Mobicom 2006, IEEE WOWMOM 2006, IEEE PerCom 2006, IEEE GlobeCom 2006, IEEE INFOCOM 2005, IEEE ICPCS 2004, IEEE ICPADS 2004, IEEE IPSN 2004, IEEE ISCC 2004-6, IFIP PWC 2003, IFIP Networking 2004-6; IEEE ICPDS 2001; IEEE ICCCN 2000-3 and others and a number of workshops.
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T-IBN:
Infrastructure-Based Wireless Multihop, Relay, Mesh Networks
Presenter: Halim Yanikomeroglu, Carleton University
Time: PM
Room: Auteuil
Abstract
Simple calculations indicate that the provision of very high data rates, beyond small pockets, is not feasible with the conventional wireless network architectures. Even the recent advances in antenna technologies (such as smart antennas and MIMO systems) and signal processing techniques (such as advanced channel coding methods) do not seem to be sufficient to alleviate the tremendous potential stress that will be incurred on the link budget in future wireless networks with the aggregate rates of 100 – 1000 Mbps. Towards that end, the augmentation of the current networks with the multihop capability is considered to be the most feasible architectural upgrade to facilitate almost ubiquitous high data rate coverage in the most cost-effective manner.
In this context, there has been growing interest in both academia and industry in the concept of relaying in infrastructure-based wireless networks such as next generation cellular (B3G, 4G), WLAN (WiFi, HiperLAN2), and broadband fixed wireless (802.16, WiMax, HiperMAN) networks. Multihop communications can be facilitated through the use of low-power/low-cost fixed relays deployed by the service provider, or through other wireless terminals in the network. This tutorial will present the concept of relaying in infrastructure-based networks, with its fundamental dynamics, potentials and limitations. The tutorial will cover physical layer issues (including novel diversity techniques, virtual antenna arrays, and cooperative relaying), systems level issues (including multiple access, ARQ, radio resource management, coverage, capacity, and throughput) and networking issues (including intelligent routing, load balancing, and handoff).
Tutorial outline
This is a survey of almost anything related to infrastructure-based relay, multihop, and mesh networks, from physical layer, to multiple access layer, up to networking layer.
• The concept of multihop communications in wireless networks
• Historical perspective (some early information-theoretic literature)
• The underlining reasons for the emerging interest in relaying
• Analog (non-regenerative) versus digital (regenerative) relaying
• Fixed relaying versus mobile relaying
• Functionality and electronics of a relay
• Relaying in license-exempt bands
• CDMA multihop networks versus TDMA/OFDM multihop networks
• Radio resource management in multihop/relay networks
• Relaying in B3G and 4G cellular networks
• Relaying in WLANs
• Relaying in broadband fixed wireless networks
• Wireless mesh networks
• Comparing & contrasting relaying in ad hoc (infrastructureless) and infrastructure-based networks
• Novel diversity schemes in multihop networks
• Cooperative relaying
• Virtual antenna arrays (distributed MIMO systems)
• Routing in infrastructure-based multihop networks
Primary Audience
Intended for engineers/researchers in academia and industry who would like to get a first comprehensive look into this emerging network paradigm, as well as for those who are already familiar with relaying concept but would like to have a deeper understanding.
Novelty
The concept of augmenting the infrastructure-based networks with the multihop capability found great momentum in the last 3-5 years. There are exciting developments in WiMAX (802.16e), WLAN (802.11s), and cellular (4G) networks towards that end. The literature is booming in parallel. Although, there have been quite a number of tutorials on ad hoc and sensor networks, there has been no comprehensive tutorial on “infrastructure-based relay/multihop/mesh networks” before, as far as we know, at least in IEEE ComSoc conferences.
Biography
Halim Yanikomeroglu was born in Giresun, Turkey, in 1968. He received a B.Sc. degree in Electrical and Electronics Engineering from the Middle East Technical University, Ankara, Turkey, in 1990, and an M.A.Sc. degree in Electrical Engineering (now ECE) and a Ph.D. degree in Electrical and Computer Engineering from the University of Toronto, Canada, in 1992 and 1998, respectively. Dr. Yanikomeroglu was with the Research and Development Group of Marconi Kominikasyon A.S., Ankara, Turkey, from January 1993 to July 1994.
Since 1998 Dr. Yanikomeroglu has been with the Department of Systems and Computer Engineering at Carleton University, Ottawa, where he is now an Associate Professor with tenure. His research interests include almost all aspects of wireless communications with a special emphasis on infrastructure-based multihop/mesh/relay networks. At Carleton University, he teaches graduate courses on digital, mobile, and wireless communications.
Dr. Yanikomeroglu has been involved in the steering committees and technical program committees of numerous international conferences in wireless communications; he has also given several tutorials in such conferences. He was the Technical Program Co-Chair of the IEEE Wireless Communications and Networking Conference 2004 (WCNC'04). He was an Editor for IEEE Transactions on Wireless Communications during 2002-05, and a guest editor for Wiley Journal on Wireless Communications & Mobile Computing; he was an Editor for IEEE Communications Surveys & Tutorials for 2002-03. Currently he is serving as the Chair of the IEEE Communications Society’s Technical Committee on Personal Communications (TCPC), he is also a member of IEEE ComSoc’s Technical Activites Committee (TAC). He is a member of the Advisory Committee for Broadband Communications and Wireless Systems (BCWS) Centre at Carleton University. Dr. Yanikomeroglu is a registered Professional Engineer in the province of Ontario, Canada.
Dr. Yanikomeroglu has extensive experience in giving tutorials in major international IEEE events, in the recent years he has given about a dozen such tutorials on “The Theory of Transmit Power Control and Its Implementation in 3rd Generation CDMA Systems”, “Radio Resource Management in Wireless Multimedia Networks”, and “Infrastructure-based Wireless Multihop, Relay, Mesh Networks”
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T-LJH:
RESEARCH ADVANCES IN MULTI-USER OFDM/MC-CDMA -
A HALF-DAY OVERVIEW
Presenter: Lajos Hanzo, School of ECS, Univ. of Southampton
Time: PM
Room: Argenteuil
Tutorial outline
1. A FUTURE-PROOF MULTICARRIER STANDARD FRAMEWORK[3].
This course is based on an amalgam of [1]-[4]. Multi-standard operation is an important requirement for the future generations of wireless systems. This overview commences with the portrayal of a versatile broadband multicarrier scheme, which is capable of meeting the requirements of future generations of wireless systems, by supporting backwards compatibility with the existing 2nd- and 3rd-generation systems, while also introducing more advanced techniques facilitated by the employment of Software De?ned Radios (SDR) and efficient adaptive baseband algorithms[1]-[3].
2. ADAPTIVE VERSUS SPACE-TIME CODED OFDM/MC-CDMA [2]
The presentation continues by demonstrating that Symbol-by-symbol adaptive Orthogonal Frequency Division Multiplex(OFDM) modems have the potential ofcounteracting the near instantaneous channel quality variations of wireless channels and hence attain an increased throughput in comparison to their fixed-mode counterparts. By contrast, various diversity techniques, such as Rake receivers and space-time coding, mitigate the channel quality variations in their effort to obtain a reduced BER. This overview investigates a combined system constituted by a constant-power adaptive modem employing space-time coded diversity techniques in the context of both OFDM and MCCDMA. The combined system can be configured to produce a constant uncoded BER and exhibits virtually error free performance, when a turbo convolutional code is concatenated with a space-time block code. It was found that the advantage of the adaptive modem erodes, as the overall diversity-order increases[2].
3. PIC-ASSISTED CHANNEL ESTIMATION FOR SDMA-AIDED MULTIUSER OFDM [2]
OFDM systems employing multiple transmit antennas have recently drawn wide interest in the context of both space-time coded and multi-user space-division multiple access (SDMA) arrangements. A prerequisite for using coherent detection at the receiver is the availability of reliable channel transfer factor estimates. Robust parallel interference cancellation (PIC) assisted decision-directed channel estimation (DDCE) has been shown in the literature to be also applicable to scenarios, where the number of users is in excess of the number of OFDM subcarriers - normalized to the number of Channel Impulse Response (CIR) related taps to be estimated - which imposed a limitation in the context ofleast-squares assisted DDCE techniques invoked in conjunction with multiple transmit antennas. In this paper we will demonstrate that the Recursive Least-Squares (RLS) algorithm is applicable to optimizing the predictors’ coeffcients on a CIR-related tap-by-tap basis. Compared to ’robust’, non-adaptive approaches the proposed solution has the advantage of a potentially lower estimation MSE and a higher resilience to erroneous subcarrier symbol decisions[2]
4. MULTIUSER DETECTION FOR MC-CDMA [3]
In this part of the presentation a Genetic Algorithm (GA) assisted Multiuser Detector (MUD) designed for MC-CDMA is investigated in the context of frequency selective Rayleigh fading channels. The achievable BER performance of the GA assisted MUD as well as its near-far resistance are investigated for a range of parameter values. It is shown that the proposed GA assisted MUD is capable of significantly reducing the complexity in comparison to that of Verdu’s optimum MUD. For example, when supporting K = 20 users, the number of likelihood function evaluations is reduced by a factor of 1300 [3]
5. REDUCED-COMPLEXITY MAXIMUM-LIKELIHOOD COMPLEX SPHERE DECODING FOR SDMA/SDM-AIDED RANK-DEFICIENT MULTI-USER OFDM [4]
A novel Space Division Multiplexing (SDM) detection method is considered, which constitutes a list-based search method and may be regarded as an advanced extension of the Sphere Decoder (SD). Our method may be employed in the so-called over-loaded scenario, where the number of transmit antenna elements exceeds that of the receive antenna elements. Furthermore, it is suitable for high-throughput, non-constant modulus modulation schemes, such as 16 and 64-QAM. We inroduce a series of optimization rules which facilitate a substantial reduction in computational complexity. More specifically, we demonstrate that the method proposed, which we refer to as the Soft-output OPtimized HIErarchy (SOPHIE)-aided SDM detector exhibits the near-optimum performance of Log-MAP SDM detector in all considered scenarios. The associated computational complexity, which we control using two complexity-control parameters, is substantially lower than that imposed by all previously proposed methods.
6. GENETIC ALGORITHM ASSISTED JOINT CHANNEL ESTIMATION AND COMPLEX SPHERE DECODING FOR SDMA-AIDED RANK-DEFICIENT MULTI-USER OFDM [4]
Multiple-Input-Multiple-Output (MIMO) Orthogonal Frequency Division Multiplexing (OFDM) systems have recently attracted substantial research interest. However, compared to Single-Input-Single-Output (SISO) systems, channel estimation in the MIMO scenario becomes more challenging, owing to the increased number of independent transmitter-receiver links to be estimated. In the context of the Bell LAyered Space-Time architecture (BLAST) or Space Division Multiple Access (SDMA) multi-user MIMO OFDM systems, none of the known channel estimation techniques allows the number of users to be higher than the number of receiver antennas, which is often referred to as an “overloaded” scenario, owing to the constraint imposed by the rank of the MIMO channel matrix. Against this background, in this paper we propose a new Genetic Algorithm (GA) assisted iterative Joint Channel Estimation and Multi-User Detection (GA-JCEMUD) approach for multi-user MIMO SDMA-OFDM systems, which provides an effective solution to the multi-user MIMO channel estimation problem in the above-mentioned overloaded scenario. Furthermore,the GAs invoked in the data detection literature can only provide a hard-decision output for the Forward Error Correction (FEC) or channel decoder, which inevitably limits the system’s achievable performance. By contrast, our proposed GA is capable of providing “soft” outputs and hence it becomes capable of achieving an improved performance with the aid of FEC decoders. A range of simulation results are provided to demonstrate the superiority of the proposed scheme.
7. MINIMUM BER MULTIUSER DETECTION FOR MIMO-OFDM [4]
The family of minimum bit error rate (MBER) multiuser detectors (MUD) is capable of outperforming the classic minimum mean-squared-error (MMSE) MUD in term of the achievable bit-error rate (BER) owing to directly minimising the BER cost function. In this paper, we will invoke genetic algorithms (GA) for finding the optimum weight vectors of the MBER MUD in the context of multiple antenna aided multi-user OFDM. We will also show that the MBER MUD is capable of supporting significantly more users in so-called rank-deficient scenarios than the number of receiver antennas available, while outperforming the MMSE MUD.
This overview of next-generation wireless enabling techniques will be concluded with a future-proof new design paradigm, highlighting a range of open problems for the radical researcher.
Primary and Secondary Audience
Whilst this overview is ambitious in terms of providing a research-oriented outlook, potential attendees require only a modest background in signal processing and wireless communications. The mathematical contents are kept to a minimum and a conceptual approach if adopted. Postgraduate students, researchers and signal processing practitioners as well as managers looking for crossfertilisation of their experince with other topics may find the coverage of the presentation beneficial. The participants will receive the set of slides as supporting material and they may find the detailed mathematical analysis in the above-mentioned books.
During his 30-year carreer Lajos Hanzo, FRAEng, DSc, FIEEE, FIEE has held various academic and research positions in Hungary, Germany and the UK. Since 1986 he has been with the University of Southampton, where he holds the Chair of Telecommunications.
Over the years he has co-authored 12 books on mobile radio communications, published in excess of 600 research papers. Lajos has also been awarded a number of distinctions and he is an IEEE Distinguished Lecturer of both the Communications and the Vehicular Technology Society. For further information on research in progress and for associated papers and book chapters please refer to http://www-mobile.ecs.soton.ac.uk
Lajos presented short courses for example at the following IEEE conferences:
ICCS’94 in Singapore; ICUPC’95 in Tokyo; ICASSP ’96 in Atlanta, USA; PIMRC’96 in Taipei, Taiwan; ICASSP’96 in Atlanta; ICCS’96 in Singapore; VTC’97 in Phoenix,USA; PIMRC’97 Helsinki,Finland; VTC’98, Ottawa, Canada; Globecom’98 Melbourne, Australia; VTC’99 Spring Houston, USA; EURASIP Conference’99, June, 1999, Krakow, Poland; VTC’99 Fall Amsterdam, The Netherlands; VTC’2000 Spring Tokyo, Japan; VTC’2001 Spring Rhodes, Greece; Globecom’2000 San Francisco, USA; Globecom’2001 San Antonio, USA; ATAMS’2001 Krakow, Poland; Eurocon’2001, Bratislava, Slovakia; VTC’2002 Spring Birmingham Alabama, USA; VTC’2002 Fall Vancouver, Canada; ICC’2002, New York, USA; Wireless’02, Calgary, Canada; WPMC’02 Honolulu,Hawaii; ATAMS ’2002, Krakow,Poland; WCNC’03 NewOrleans,USA; VTC’2003 Spring, Jeju Island, Korea; PIMRC’2003, Beijing, China; VTC’2003 Fall Orlando,USA; VTC’2004 Spring, Milan, Italy; European Wireless Conference’ 2004, Barcelona, Spain; ICC’2004, Paris, France; EUSIPCO’2004, Vienna, Austria; European Wireless Conference’2005, Nicosia, Cyprus; VTC’05 Spring Stockholm, Sweden; VTC’05 Fall, Dallas, USA; WPMC’2005 Aalborg, Denmark; VTC’2006 Spring Melbourne, Australia; ICC’2006 Istanbul, Turkey;
He is also the presenter of an IEEE COMSOC ’voice over powerpoint’ www tutorial.
8. REFERENCES
[1] L. Hanzo, T.H. Liew, B.L. Yeap: Turbo Coding, Turbo Equalisation and Space-Time Coding, John Wiley, August 2002, ISBN 0-470-84726-3, p 766
[2] L. Hanzo, M. M¨unster, B.J. Choi and T. Keller: OFDM and MC-CDMA for Broadband Multi-user Communications, WLANs and Broadcasting, John Wiley -IEEE Press, May 2003, 1010 pages
[3] L. Hanzo, L-L. Yang, E-L. Kuan and K. Yen: Single-and Multi-Carrier CDMA: Multi-User Detection, Space-Time Spreading, Synchronisation, Standards and Networking, IEEE Press -John Wiley, June 2003, 1060 pages
[4] L. Hanzo, T. Keller: An OFDM Primer, John Wiley -IEEE Press, May 2006, 426 pages.