Tutorials offered at VTC2009-Spring

Sunday 26 April 2009 

Note room and time updates. Tutorial T3 has been cancelled.

T1: Iterative Receiver Design
Presented by: Dr. Henk Wymeersch, Massachusetts Institute of Technology, USA
Time: 9:00–12:30
Room: Adriatic

Abstract
Many researcher, students, and practicing engineers are familiar with iterative,
turbo-style processing but still often lack the knowledge of the underlying mathematical
framework. In this tutorial, we will provide a rigorous, yet accessible introduction to the
framework of factor graphs and how it can be used in developing iterative algorithms for
estimation and detection. We emphasize the use of the factor graphs for the design of
iterative receivers, with applications in decoding (e.g., turbo and LDPC codes), MIMO
detection, multi-user detection, and synchronization. This tutorial contains many examples and exercises.

Tutorial Objectives
More and more researchers work on iterative algorithms and see them as magical tools with extrinsic, intrinsic, and a priori information passing back and forth. Such a black-box approach leads to misconceptions, vast differences in notation and terminology, and does not reveal deeper connections between different algorithms. The main motivation of this tutorial is to fill this knowledge gap in the wireless communications and signal processing communities. With the aid of graphical models, this tutorial will show that many iterative algorithms are special cases of a general framework. This framework is both elegant and remarkably uncomplicated, and will enable researchers and students to think about algorithms in a very different, more systematic way. The concrete objectives of this proposal are to: (i) understand optimal detection; (ii) understand factor graphs and message passing, and their application to optimal detection; (iii) understand that many algorithms for detection and estimation can be seen as special of message passing on an appropriate factor graph; (iv) become familiar with the practical implementation of message passing algorithms; (v) be able to create factor graphs for new problems, and extend the knowledge from this tutorial to other problems beyond receiver design.

Tutorial Outline

1. Digital Data Transmission

2. Optimal Detection and Estimation

3. Factor Graphs and the Sum-Product Algorithm

4. Statistical Inference with Factor Graphs

5. Iterative Receiver Design

6. Advanced topics in distributed processing

Primary Audience
This tutorial is aimed at graduate students, academic researchers, and practitioners in the field. Background knowledge is limited to basic probability and notions of communication theory.

Novelty
This tutorial describes the framework of graphical models for turbo processing in a systematic, rigorous fashion, without being distracted by myriad of ad-hoc variations of turbo processing.

Biography
Henk Wymeersch is a postdoctoral associate with the Laboratory for Information and Decision Systems (LIDS) at the Massachusetts Institute of Technology (MIT). His research interests include algorithm design for wireless transmission, statistical inference and iterative processing. He obtained the Ph.D. degree in electrical engineering in 2005 from Ghent University, Belgium. In 2005-2006, Henk Wymeersch was a postdoctoral fellow of the Belgian American Educational Foundation at MIT, and in 2006 he won the Alcatel Bell Scientific Award for his Ph.D. thesis. He is a member of the IEEE, associate editor for IEEE Communication Letters, for the Journal of Computer Systems, Networks, and Communications, and author of Iterative Receiver Design (Cambridge University Press, August 2007).

T2: Future Gigabit/s Systems: Towards Real 4G and Cognitive Radios
Presented by: Dr. Nicola Marchetti, Aalborg Univ, Denmark, and Dr. M. Imadur Rahman, Ericsson Research, Sweden
Time: 14:00–17:30
Room: Adriatic

Abstract
Next generation wireless systems are supposed to reach ambitious targets in terms of data rate and spectrum efficiency, which can be fulfilled only if a sufficient degree of intelligence and adaptivity can be put into future radios. This tutorial will address a number of intelligent and autonomous techniques that can be implemented in future wireless systems to realize such efficient high rate networks.
After a general introduction on future Gigabit/s systems, some advanced PHY and RRM techniques suitable for achieving "real" 4G targets in terms of data rate and spectral efficiency will be given, keeping especially an eye on smart and flexible design. The concentration will be on multi-antenna techniques, cognitive radios, advanced spectrum management, adaptive scheduling etc. Specifically, challenges and benefits related to flexible and smart spectrum utilization, spectrum sharing and cognitive radio techniques will be touched, as complementary and evolved technologies with respect to the above-mentioned PHY and RRM architectures.

Tutorial Objectives
The tutorial touches on several topics, all related to smart and flexible design for next generation wireless systems. The participants will get familiar with the "real" 4-th generation, that is about to come into the market, from PHY and RRM perspectives. Furthermore, a glance on cognitive radio technology and advanced spectrum management will be given, providing the audience with an idea of a timely and hot research topic.

Tutorial Outline

1. Introduction: The future of Gbps Wireless Systems

2. Standards

3. Advanced techniques for future wireless systems

4. Spectrum sharing and cognitive radio

5. Radio frequency and PHY issues for Flexible Spectrum Usage

6. Advanced RRM for spectrum sharing: Spectrum Load Balancing

7. Advanced RRM for spectrum sharing: Game theoretical-approach to Cognitive Radio

8. Conclusion, Future Visions and Wrap-up

Primary Audience
1. Graduate students interested in PHY and MAC layer design.
2. Academic and industry researchers, system developers, interested in design and development.
3. Industry professionals and system engineers who are involved in developing and maintaining broadband systems.

Novelty
The issues touched in the tutorial, i.e. Gigabit/second and Cognitive Radio technologies are among the hottest and most timely research topics in the field of Wireless Communications, and in fact have been chosen as the two pillars of the tutorial's structure.

Biography
Nicola Marchetti was born in Legnago, Italy, on October 2, 1978. In 2003 and 2007 he received the M.Sc. degree in electronic engineering and the Ph.D. degree in wireless communications from University of Ferrara, Italy, and Aalborg University, Denmark, respectively. From July 2003 to April 2004 he was a research assistant at the University of Ferrara and he worked a PhD Researcher from May 2004 to May 2007 at Aalborg University Denmark. Since June 2007, he is a Research Assistant Professor at Aalborg University, working on projects related to flexible spectrum usage and cognitive radios. He is a member of the Advisory Committee on Applied Mathematics at Aalborg university (AMAAU). In 2008, he was TPC-chair of the First International Workshop on Cognitive Radio and Advanced Spectrum Management (CogART) and General Co-Chair of the First International Symposium on Applied Sciences in Biomedical and Communication Technologies (ISABEL). He was lecturer in Electric Communication at the University of Ferrara, and he has been successfully supervising nine M.Sc. students. He is currently supervisor of three Ph.D. and six M.Sc. students. His research interests include: multiple antenna technologies, single- and multi-carrier modulations, radio resource management, cognitive radios and advanced spectrum management techniques, applied mathematics for wireless communication.
Muhammad Imadur Rahman was born in Bangladesh on 30 January 1976. He obtained his PhD degree in Wireless Communications from Aalborg University Denmark on September 2007. Prior to that, he obtained his B.Sc degree in Electronics Engineering in 2000 from Multimedia University Malaysia and MSc degree in Radio Communications from Helsinki University of Technology Finland in 2003. Since the beginning of 2003, he was employed as a researcher in Aalborg University. He was an assistant professor in the same university in 2007, where he taught a number of MSc level courses in mobile communications, supervised 10 MSc students and 3 PhD students. Currently he is with Ericsson Research, Kista, Sweden since January 2008 working as a research engineer in Access Technologies and Signal Processing group. His main research interest is multiple access techniques, multi-antenna ssues, spectrum sharing and radio resource management in wireless systems. He has been involved in a number of conferences and workshops as organizing and technical committee member. He is an active IEEE volunteer.

T3: Mobility and Multiaccess in Emerging Internet Architectures
Presented by: Dr. Kostas Pentikousis, VTT Technical Research Centre of Finland
Time: 9:00–12:30
Room: CANCELLED

Abstract
Popular mobile devices now ship with several integrated wired and wireless network interfaces. PDAs and smartphones, for example, are increasingly supporting communications via both cellular technologies and wireless LANs; laptops typically come with built-in Ethernet, Wi-Fi and Bluetooth. As multiaccess devices proliferate, we move closer to a network environment that is often referred to as ``beyond 3G", or B3G in telecommunications speak.

This tutorial thoroughly reviews recent developments in mobility and multiaccess technologies. After motivating the need for novel mechanisms to meet the challenges from the emerging network environment, the tutorial introduces the recently finalized Media Independent Handover Services standard (IEEE 802.21) and presents a blueprint for its implementation. Finally, the tutorial introduces recent developments in the so-called clean-slate Internet architecture design space, presenting the new paradigms, and elaborating on their impact on mobility and multiaccess.

Tutorial Objectives
Key success factors for cellular 3G communications include better cell capacities, increased data rates, seamless mobility within large geographical areas, and global reachability. For B3G, the next frontier lies beyond seamless mobile connections within the same access technology. Instead, users will soon expect to be globally reachable round the clock and ``best-connected" as well. In order to select the best possible connectivity option (anytime, anywhere), mobile devices and access networks will have to work together, thus enabling users to make the most of all available options. Given the diversity of networked applications running on mobile devices there is a call for knowledgeable network resource planning and operation. In other words, there is a need for a framework that allows users and their applications to state their network access preferences. This framework should also allow operators to steer terminal access patterns aiming at maximizing resource utilization and increasing user satisfaction. For instance, podcasts can be downloaded only when connected to an uncongested. WLAN, but web, map/navigation, and email clients can use the cellular network or WLAN access on demand. Currently, this can only be done manually: users need to be on the lookout for available access networks and choose which one to attach to based on very rudimentary information such as signal quality. If mobile nodes could collect timely and consistent information about the state of all available networks in range, and were given the means to control their network connectivity, then a whole range of possibilities opens up. The first objective of this tutorial is to introduce a whole line of work in this area in a concise manner, emphasizing on recent developments. In order to optimize the use of available network resources, mobile nodes need to be able to collect information on a number of heterogeneous networks in a generic and standardized way, irrespective of the underlying network access technology. The collected information, both dynamic and static, can then be utilized by handover decision making processes, such as, say, mobility managers. Mobility managers can be enhanced versions of Mobile IP, proprietary solutions, or other proposals stemming from research projects. Researchers in the area have proposed several cross-layer frameworks for enhancing the efficiency of handover decision makers, reviewed in the second part of this tutorial titled ``Mobility and Multiaccess Foundations", but none of them has been formally standardized or is widely accepted so far. What is needed is a standard framework, which can attract ample support from major vendors and operators, and can be deployed in an incremental manner. This framework, introduced in the third part of the tutorial, is IEEE 802.21. Thus the second objective of this tutorial is to present the recently-finalized standard specification and introduce the participants to the implementation issues that arise. Finally, the third tutorial objective is to relate emerging Internet architectures with the IEEE 802.21 standard. As multiaccess proliferates and new Future Internet paradigms are proposed we will explore new directions for future research in the area. The tutorial will also include background material on ongoing projects in the area of Future Internet research.

Tutorial Outline

1. Introduction

2. Mobility and Multiaccess Foundations

3. IEEE 802.21: Specification

4. IEEE 802.21: Implementation

5. Emerging Internet Architectures

Primary Audience
Scientists and engineers; telecom researchers and practitioners; network managers, service developers, and R&D staff; postgraduate students.

Participants will receive the set of slides as supporting material along with an extensive set of references for further study.

Tutorial Level: Intermediate.

Novelty
This tutorial covers the work in this area of mobile computing in a concise manner, distilling seminal results, positioning ongoing work, and identifying open problems. It covers IEEE 802.21 in terms of both standard specification and implementation, and presents emerging Internet architectures, providing the necessary background along the way. In this respect, this tutorial is unique as it allows participants to gain a complete view of recent developments on mobility and multiaccess for Internet architectures and should be in particular most valuable for those considering new lines of research for future work.

Biography
Kostas Pentikousis is a tenured Senior Research Scientist at VTT Technical Research Centre of Finland. He has been working in research and development positions since 1996 in both industry and academia. Dr. Pentikousis joined VTT in 2005 and has since been involved in several joint and contract research projects, including Ambient Networks, WEIRD, and 4WARD. Kostas studied computer science at Aristotle University of Thessaloniki (BS 1996; summa cum laude) and Stony Brook University (MS 2000, PhD 2004). He has published more than 70 papers in several areas, including mobile computing, transport protocols, applications, network traffic measurements and analysis, and simulation and modeling. He recently presented tutorials at APNOMS 2005, ISCC 2006, and MUM 2008. Kostas serves on the TPC of various conferences and reviews papers for journals and conferences on a regular basis. For more information visit http://ipv6.willab.fi/kostas/

T4: Communication protocols in vehicular networks
Presented by: Professor Ivan Stojmenovic, University of Ottawa, Canada
Time: 14:00–17:30
Room: Baltic

Abstract
Tutorial deals with the vehicle-to-vehicle (V2V) and vehicle-infrastructure (V2I and I2V) data communication issues. The problems covered include geocasting for congestion notification (broadcast warning and traffic information to all vehicles on a road segment or in given area, suppress multiple warning for the same event, determine boundaries for warning spreading), routing (V2V, V2I, I2V) for communication between two cars or car tracking, and enabling application services by user devices (supporting Internet connections between users and service providers in a mobile environment). All protocols deal with intermittently connected network of vehicles, whose nature is also discussed. Routing and geocasting protocols with and without the use of RSU (road side units) are covered.

Tutorial Objectives
The objective is to describe communication protocols that move traffic data and requests from vehicles to servers and responses and commands from servers to vehicles. Drivers need to be informed about all kinds of events and conditions that impact their travel. For example, they need to be informed about traffic congestion, slippery road conditions, rain, and so on. Though an ITS system should guide drivers along the best possible paths, it is important to keep drivers informed so that they know why they are taking such routes. Geocasting involves the broadcasting of information to all vehicles on a road segment or in a given geographic area, suppressing multiple warnings for the same event, and determining boundaries for spreading warnings. It is an important communication function. Geocasting is initiated by one vehicle or one RSU. The source of information intended for geocasting may or may not be located in the geocasting region. For example, reports on congestion on a highway segment may be useful to vehicles approaching a previous exit, and not necessarily to the vehicles already in the congested area. The primary mechanism to fulfill geocasting is broadcasting, which spreads the information without considering the region borders. When the discussion is not concerned about border issues, the task is frequently called broadcasting, or warning delivery, or data dissemination. Novel ITS applications will require wireless communication between two vehicles, such as belonging to response teams, for car tracking, or two ordinary drivers. Extended communication between two vehicles on the road will be provided via other vehicles and RSUs. This is known as the routing task.

Tutorial Outline

Vehicular ad hoc networks, V2V and V2I
Physical, MAC and transport layers.

Broadcasting and geocasting for congestion notification in VANET

V2V and V2I Routing in VANET
Bringing Internet into vehicles

Mobility models and connectivity characteristics

An architecture for the notification of traffic incidents

Primary Audience
Researchers (including graduate students) in computing, engineering and mathematics disciplines. No particular background preparation needed.

Novelty
Tutorial covers up to date V2V and V2I communication protocols. It appears to be among the first tutorials on the timely topic, which is subject to active recent research by several groups from all continents. The emphasis is on explaining how best known solutions actually work, giving examples, discussing their advantages and drawbacks.

Biography
Ivan Stojmenovic received Ph.D. degree in mathematics. He held positions in Serbia, Japan, USA, Canada, France, Mexico, Spain and UK (as Chair in Applied Computing at the University of Birmingham, UK), and is Full Professor the University of Ottawa, Canada. He published over 250 different papers, and edited four books on wireless, ad hoc and sensor networks and applied algorithms with Wiley/IEEE. He is currently editor of over dozen journals, and founder and editor-in-chief of three journals (Journal of Multiple-Valued Logic and Soft Computing, International Journal of Parallel, Emergent and Distributed Systems, and Ad Hoc & Sensor Networks, An International Journal). Stojmenovic is in the top 0.56% most cited authors in Computer Science (Citeseer 2006). One of his articles was recognized as the Fast Breaking Paper, for October 2003 (as the only one for all of computer science), by Thomson ISI Essential Science Indicators. He is recipient of the Royal Society Research Merit Award, UK. He is recently elected to IEEE Fellow status (Communications Society, class 2008). He chaired and/or organized >30 workshops and conferences, and served in over 100 program committees since 2004. Among others, he was/is program co/vice-chair at IEEE PIMRC 2008, IEEE AINA-07, IEEE MASS-04 and -07, EUC-05 and -08, WONS-05, MSN-05 and -06, ISPA-05 and -07, founded workshop series at IEEE MASS, IEEE ICDCS and IEEE DCOSS, and Workshop Chair at ACM Mobicom/Mobihoc 2007 and ACM Mobihoc 2008. He presented over dozen tutorials.

T5: HSDPA, HSUPA and MIMO-aided cross-layer-optimized FDD versus TDD networking for Green Radio
Presented by: Professor Lajos Hanzo, University of Southampton, UK; http://www-mobile.ecs.soton.ac.uk
Time: 9:00–12:30
Room: Marmara

Abstract
This research-oriented presentation is based on the Wiley/IEEE Press monographs and considers the joint benefits of both adaptive physical and adaptive network-layer performance enhancement techniques, with special emphasis on the latter. More specifically, conventional systems would drop a call in progress, if the communications quality falls below the target quality of service and it cannot be improved by handing over to another physical channel. By contrast, the adaptive transceivers of the near future are expected to simply instantaneously drop the throughput, rather than dropping the call by reconfiguring themselves in a more robust mode of operation. It is demonstrated that the proposed beam-forming and adaptive transmission techniques may double the expected tele-traffic capacity of the system, whilst maintaining the same AVERAGE performance as their conventional fixed-mode counterparts. We explore the inherent implications of the bandwidth versus power efficiency criteria routinely employed to characterize wireless communication systems. We stress the pressing importance of the power efficiency-related green radio considerations in the context of contemporary as well as future wireless networks. Finally, we carry out a topdown analysis of a hypothetical commercial wireless network and demonstrate that the appropriate choice of the optimization criterion has a profound influence on the overall network performance. A brief list of topics is provided below:
o Key features of HSDPA/HSUPA;
o FDD versus TDD principles;
o Hand-overs and their associated queues;
o Power control;
o Adaptive modulation and coding;
o Transmit and receive beam-forming;
o Network performance metrics;
o Performance results;

Tutorial Objectives
1. Understand the key features of HSDPA/HSUPA; 2. Become cognizant with the FDD versus TDD principles; 3. Discuss hand-overs and their associated queues; 4. Understand the principles of power control; 5. Familiarize participants with adaptive modulation and coding; 6. Quantify the benefits of transmit and receive MIMO-aided beam-forming; 7. Study pertinent network performance metrics; 8. Quantify the achievable performance.

Tutorial Outline

1. Introduction

2. FDD Versus TDD Aided Networks

3. The Network-Layer Benefits of Loosely Synchronized Spreading Codes

4. Genetically Enhanced Performance of a UTRA-like TDD CDMA Network

5. Large Area Synchronized Codes in ad hoc Networks

6. Random Ad Hoc Networks Using Rate Adaptation

7. Performance of MIMO-aided HSPA networks

Primary Audience
Whilst this overview is ambitious in terms of providing a research-oriented outlook, potential attendees require only a modest background in wireless networking and 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 cross-pollination of their experience 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.

Novelty
A digest of many of the 3GPP RAN long-term evolution topics is interpreted in an readily accessible light-hearted style.

Whilst the performance benefits of either physical or network-layer solutions are typically quantified in isolation, this research overview considers them jointly.

Both TDD and FDD systems are considered and their benefits and disadvantages are studied.

Recent research advances on Large Area Synchronized (LAS) spreading sequences are presented.

Familiarization with next-generation system concepts.

Highlight the related channel access and networking solutions

Biography
Lajos Hanzo (http://www-mobile.ecs.soton.ac.uk) received his first-class Master degree in electronics in 1976, his PhD in 1983 and his Doctor of Sciences (DSc) degree in 2004. He is a Fellow of the Royal Academy of Engineering (FREng). During his career in telecommunications he has held various research and academic posts in
Hungary, Germany and the UK. Since 1986 he has been with the School of
ECS, University of Southampton, UK, where holds the Chair in Telecommunications.
He co-authored 15 IEEE Press - John Wiley books totaling in excess of 10 000 pages on mobile radio communications, published in excess of 800 research papers, organized and chaired conference sessions, presented overview lectures and has been awarded a number of distinctions. Currently he heads an academic research team, working on a range of research projects in the field of wireless multimedia communications sponsored by industry, the Engineering and Physical Sciences Research Council (EPSRC) UK, the European IST Program and the Mobile Virtual Centre of Excellence (VCE), UK. He is an enthusiastic supporter of industrial and academic liaison and he offers a range of industrial courses. Lajos is also an IEEE Distinguished Lecturer and a Fellow of both the IEE and IEEE. Lajos is the Editor-in-Chief of the IEEE Press. For further information on research in progress and associated publications please refer to http://www-mobile.ecs.soton.ac.uk/

T6: Multiuser MIMO Communications in Theory and Practice
Presented by: Dr. Gerhard Bauch and Dr. Guido Dietl, DOCOMO Euro-Labs, Germany
Time: 14:00–17:30
Room: Marmara

Abstract
Multiuser multiple-input multiple-output (MIMO) will be the next step in practical implementations of multi-antenna transmission methods in commercial systems. A very simple version of multiuser MIMO has already been standardized in 3GPP Long Term Evolution (LTE). Multiuser MIMO is likely to play a major role in standardization of 4G systems like 3GPP-LTE-Advanced and IMT-Advanced. The tutorial is based on both the authors scientific/theoretical work and their active participation in standardization in 3GPP.
We will give an introduction to multiuser MIMO techniques which aim at increasing the sum capacity and spectrum efficiency of the downlink of wireless communications systems. We will report the most important theoretical limits and methods in order to approach those limits. However, the focus of the tutorial is on practical aspects. Since multiuser MIMO has become a topic in standardization for 3GPP-LTE, we concentrate on multiuser MIMO methods and problems which have been discussed in 3GPP-LTE and lead to the respective decisions. This particularly includes design of feedback information, codebook design, actual precoding, receiver processing, and scheduling.
We will show which features of 3GPP-LTE limit the achievable gains by multiuser MIMO. Furthermore, we will make proposals for modifications and extensions in order to obtain substantial performance gains by multiuser MIMO which could be exploited in 3GPP-LTE-Advanced and IMT-Advanced systems. We will also discuss possible application scenarios and services.

Tutorial Objectives
A major goal of this tutorial is to bridge the gap between academic research and industrial application. Based on the authors background from working in a company’s research department with both close collaboration with universities and their active participation in the standardisation of 3GPP-LTE, the tutorial tries to give both an introduction to the theoretical basis of multiuser MIMO as well as to practical problems and solutions which have the potential to make their way into standards. 3GPP-LTE and LTE-Advanced will be used as exemplary framework. We will start with a description of performance targets for IMT-Advanced or 3GPP-LTE-Advanced, respectively, and will demonstrate that advanced MIMO is an indispensible ingredient in order to meet those targets even under perfect conditions. We will then explain the principles of MIMO modes in LTE with a focus on closed-loop schemes. The baseline in LTE is single-user (SU) MIMO, i.e. users are separated by means of OFDMA and TDMA but not by spatial separation. However, LTE includes already a very simple form of multiuser (MU) MIMO where SDMA is possible. In the uplink this is mainly a scheduling problem. However, in the downlink the precoder has to take care of inter-user interference. Therefore, we focus on MU-MIMO for the downlink. We will explain the potential benefits of MU-MIMO over SU-MIMO and describe the solution which is included in LTE. The relatively poor performance of this solution will be demonstrated and explained mainly by the too small feedback of channel state information. This motivates to look for better MU-MIMO solutions. We will now give an introduction to information theoretic limits in order to demonstrate the potential of MU-MIMO. We will present non-linear MU-MIMO algorithms which aim at performance close to those limits. This part of the tutorial will be supported by a software demonstration. This part will also include an introduction to dirty paper coding and an intuitive explanation of Tomlinson-Harashima precoding as a simple implementation of dirty paper coding. Finally, we will consider linear MU-MIMO schemes and will show that linear schemes can achieve performance reasonably close to capacity approaching non-linear schemes while having significantly lower complexity. We will particularly focus on limited feedback schemes including precoder or channel vector quantization codebook design. This is motivated by the fact that the amount of feedback bits is a major restriction in commercial systems. We will compare theoretical limits and various MU- and SU-MIMO schemes in terms of achievable rates and complexity. Rate distribution among users, fairness and possible application scenarios will also be discussed.

Tutorial Outline

Introduction
MIMO for bandwidth-efficient wireless communications
Multiuser diversity
Single-user (SU) MIMO versus multiuser (MU) MIMO
Uplink MU-MIMO versus downlink MU-MIMO
Linear versus non-linear MU-MIMO

Single-user MIMO
Spatial multiplexing with Rx and Tx processing

Theoretical fundamentals
Introduction to dirty paper coding (DPC)
Tomlinson-Harashima precoding (THP)
Precoding for the MIMO broadcast channel

Non-linear MU-MIMO algorithms based on dirty paper coding (DPC) and zero-forcing (ZF)
Sequential encoding with DPC and ZF for single receive antennas
Sequential encoding with DPC and block zero-forcing (block ZF)
SESAM: A capacity approaching algorithm
Comparison of achievable rates

Theoretical limits
Capacity of the SU-MIMO channel
Capacity region of the MIMO multiple-access channel (MAC)
Sum capacity of the MIMO broadcast channel (Sato bound)
DPC and dual MAC region of the MIMO broadcast channel
Capacity region of the MIMO broadcast channel

Linear MU-MIMO schemes for 3GPP Long Term Evolution (LTE) and 3GPP-LTE-Advanced
Linear versus nonlinear precoding
Summary of MIMO techniques in 3GPP-LTE
MU- versus SU-MIMO
Unitary precoding with precoder codebook
ZF precoding with channel codebook
Standardized 3GPP-LTE MU-MIMO scheme
Performance comparisons

Conclusions

Primary Audience
This tutorial addresses engineers in industry and academia who are looking for an overview on multiuser MIMO and are particularly interested in problems and solutions which are discussed in standardization. There is no special background required since brief reviews of the basics will be presented. However, the tutorial also contains material for people with a background in multiuser MIMO such as theory, advanced algorithms, and standardization.

Novelty
Compared to many tutorials in the field of multiuser MIMO communications, this tutorial covers both an introduction to the theoretical basis of multiuser MIMO as well as to practical problems and solutions which have the potential to make their way into standards like, e.g., 3GPP-LTE-Advanced or IMT-Advanced.

Biography
Dr. Gerhard Bauch received the Dipl.-Ing. and Dr.-Ing. degree in Electrical Engineering from Munich University of Technology (TUM) in 1995 and 2001, respectively, and the Diplom-Volkswirt degree from FernUniversitaet Hagen in 2001. In 1996, he was with the German Aerospace Center (DLR), Oberpfaffenhofen, Germany. From 1996-2001 he was member of scientific staff at Munich University of Technology (TUM). In 1998 and 1999 he was visiting researcher at AT&T Labs Research, Florham Park, NJ, USA. In 2002 he joined DOCOMO Euro-Labs, Munich, Germany, where he is currently manager of the Advanced Radio Transmission Group. In 2007 he was additionally appointed Research Fellow of DoCoMo Euro-Labs. Since October 2003 he has also been an adjunct professor at Munich University of Technology. In 2007 he was a visiting professor teaching courses at the University of Udine in Italy and at the Alpen-Adria-University Klagenfurt in Austria.
He received the best paper award of the European Personal Mobile Communications Conference (EPMCC) 1997, the Texas Instruments Award of TUM 2001, the award of the German Information Technology Society (ITG in VDE) 2002 (ITG Foerderpreis) and the literature award of the German Information Technology Society (ITG in VDE) 2007 (ITG-Preis).

Dr. Guido Dietl received the Dipl.-Ing. and Dr.-Ing. degree (both summa cum laude) in Electrical Engineering from Munich University of Technology (TUM), Munich, Germany, in 2001 and 2006, respectively. He has been with the TUM from 2001 to 2006 where he was working as a Research Engineer on reduced-rank signal processing in Krylov subspaces and on its application to wireless multiuser communications. In Winter 2000/2001 and Summer 2004, he was a Guest Researcher at Purdue University, West Lafayette, IN, USA. In Fall 2005, he visited the Australian National University (ANU) in Canberra, ACT, Australia. He joined DOCOMO Euro-Labs, Munich, Germany, in 2006, where he is currently Senior Researcher of the Wireless Technologies Research Group.
Dr. Dietl received the VDE Award for his diploma thesis in 2001, the Kurt Fischer Award of TUM for his doctoral thesis in 2007 and the award of the German Information Technology Society (ITG in VDE) 2007 (ITG Foerderpreis).

T7: Mobile Network Cooperation at Its Best in Beyond 3G: Network Composition
Presented by: Dr. Roch Glitho, Concordia University and Ericsson, Canada
Time: 9:00–12:30
Room: Baltic

Abstract
Mobile network cooperation is well known in cellular networking where networks belonging to different operators cooperate to give roaming end-users seamless access to basic services. However mobile network cooperation as known today is not yet at its best. It relies on substantial off-line agreements and cumbersome manual configurations. Network composition is an emerging concept that brings network cooperation to its best. It is rooted in ambient networking, a beyond 3G networking approach proposed by a European Union 6th Framework project. It enables scalable and dynamic cooperation between heterogeneous networks and seamless access to new services. Off-line agreements and manual configurations are non existent or kept to a bare minimum. This tutorial is devoted to network composition. We start by discussing roaming in 3G cellular networks and pinpointing the shortcomings. This is followed by an introduction to ambient networking, the setting for network composition. We then discuss the principles, protocols and algorithms of network composition. A concrete case study on registry composition is finally presented for illustration purpose.

Tutorial Objectives
Two major goals are assigned to this tutorial: 1. Introduce roaming in the IP multimedia subsystem (IMS) of 3G networks and the shortcomings. 2. Present the more general concept of network cooperation that is emerging for beyond 3G as part of the ambient networking concept and show how this novel concept addresses the shortcomings of roaming in 3G The attendees will get acquainted with the following: - Shortcomings of roaming as known today in IMS. - Ambient networking - Network composition including composition degrees and procedures - Registry composition

Tutorial Outline

1. Introduction

2. Network cooperation in 3G
a. The IP Multimedia Sub-System (IMS)
b. Cooperation at the control layer of IMS including scenarios
c. The drawbacks

3. Ambient networking as the setting for network composition
a. Overall architecture of ambient networks
b. Media delivery as example of ambient network functional entity

4. Network composition
a. Composition degrees and scenarios
b. Composition procedure
c. Signalling for composition

5. Registry composition as a case study
a. Problem statement, scenarios and procedures
b. Negotiation for registry composition
c. Signalling for registry composition

6. Conclusions

Primary Audience
This tutorial is designed to appeal to a wide range of audience. R&D telecommunications engineers, telecommunications managers, academic researchers and graduate students will benefit from attending the tutorial.

Novelty
It is the very first tutorial that discusses the shortcomings of roaming in 3G and present how these shortcomings are being addressed in beyond 3G

Biography
Roch H. Glitho [SM] (http://www.ece.concordia.ca/~glitho/) holds a Ph.D. (Tekn. Dr.) in tele-informatics (Royal Institute of Technology, Stockholm, Sweden) and M.Sc. degrees in business economics (University of Grenoble, France), pure mathematics (University Geneva, Switzerland), and computer science (University of Geneva). He works in Montreal, Canada, as an Expert at Ericsson, and as an Adjunct Associate Professor at Concordia University where he teaches a graduate course on next generation networks. In the past he worked as a Senior Specialist in network management for Ericsson Telecom in Stockholm, and as an R&D engineer for a computer manufacturer in Oslo, Norway. His industrial experience includes research, international standards setting (e.g. contributions to ITU-T, ETSI, TMF, ANSI, TIA, and 3GPP), product management, project management, systems engineering and software/firmware design. He is an IEEE distinguished lecturer a senior technical editor of IEEE Communications Magazine and a technical editor of IEEE Communications Surveys and Tutorials. In the past he has served as Editor-In-Chief of IEEE Communications Magazine and IEEE Communications Surveys & Tutorials Magazine. His research areas include architectures for end-users services, network management, signalling and mobile code. In these areas, he has authored around 80 peer-reviewed papers, more than fifteen of which have been published in well-known refereed journals. He has also guest-edited some 10 special issues of refereed journals and has more than 20 patents in the aforementioned areas.

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