Cognitive Radio as an Advanced Radio Resource Management
15 May 2008 (AM)
Prof. Seiichi Sampei, Osaka University, Japan
Cognitive Radio is a new concept for the future Information and telecommunications networks, and it is expected as a breakthrough for shortage of spectrum as well as a technique to guarantee Quality of Services for each user in ubiquitous and heterogeneous networks. In this tutorial, we will focus mainly on how the cognitive radio should be introduced in wireless communication networks, especially, as an advanced radio resource management. In this tutorial, after brief discussion on the basic concept of cognitive radio, the concept of radio resource management is explained and then what is the advanced spectrum sharing based on cognitive radio will be explained. Finally, relationship between the cognitive radio and heterogeneous networks will also be explained.
Seiichi Sampei received the B.E., M.E. and Ph.D. degrees in electrical engineering from Tokyo Institute of Technology, Japan, in 1980, 1982 and 1991, respectively. From 1982 to 1993, he was engaged in the development of adjacent channel interference rejection, fast fading compensation and M-ary QAM techniques for land-mobile communication systems, as a researcher in the Communications Research Laboratory, Ministry of Posts and Telecommunications, Japan. During 1991 to 1992, he was at the University of California, Davis, as a visiting researcher. In 1993, he joined the Faculty of Engineering, Osaka University, and he is currently a Professor in the department of Information and Communications Technology, Osaka University, where he has developed adaptive modulation, intelligent radio transmission/access, and cognitive wireless networking techniques. He received the Shinohara Young Engineering Award, and the Achievements Award from the IEICE (Institute of Information and Communication Engineers), the Telecom System Technology Award from the Telecommunication Advancement Foundation, and the DoCoMo Mobile Science Award from Mobile Communication Fund. He is a member of the Institute of Image Information and Television Engineers (ITE), and a Fellow of the IEEE and Institute of Electronics, Information and Communication Engineers (IEICE).Top
Cognitive Wireless Networks
15 May 2008 (AM)
Prof. Petri Mähönen, RWTH Aachen University, Germany
Janne Riihijärvi,RWTH Aachen University, Germany
Marina Petrova, RWTH Aachen University, Germany
This tutorial starts by giving a brief historical background on the cognitive radios. We describe what is meant by spectrum agile radios and by full cognitive radios ("Mitola Radios"). From cognitive radios we then move on to basic concepts of cognitive wireless networks. The emphasis will be on covering recent research results and remaining key research challenges towards creation of such networks. We cover briefly game theory and other classical approaches, but our focus here will be on the use of metaheuristics and machine learning algorithms for full cross-layer and network wide optimization. We shall also discuss in some detail applications of topology and geometry information in the optimization process. As a part of the discussion, a brief introduction to modern spatial statistics techniques will be provided. The tutorial is emphasizing architectural concepts and emerging new methodologies. The tutorial also provides attendees with knowledge of the most important concepts and open research questions in this emerging field. As such it is also suited for beginning graduate students.
Petri Mähönen is currently a full professor and holds Ericsson Chair of Wireless Networks at the RWTH Aachen University in Germany. Before joining to RWTH Aachen in 2002, he was a research director and professor at the Centre for Wireless Communications and the University of Oulu, Finland. He has studied and worked in the United States, United Kingdom and Finland. He has been a principal investigator in several international research projects, including initiating and leading several large European Union research projects. Dr. Mähönen has published ca. 150 papers in international journals and conferences and has been invited to deliver research talks at many universities, companies and conferences. He is a senior member of IEEE and ACM, and fellow of RAS. He is inventor or co-inventor for over 20 patents or patent applications. He has been particularly active in cognitive wireless network research and has been serving in different roles in relevant cognitive communications domain conferences, such as DySPAN, CogNet and CrownCom. He has been also guest-editor for several special issues in the field. He is currently also a research area coordinator and one of the principal investigators for a newly formed Ultra High Speed Mobile Information and Communication (UMIC) research cluster at RWTH, which is one of the German national excellence clusters supported by the Federal Government of Germany established in 2006. One of the research domains in UMIC cluster is also cognitive radio network technologies.
Janne Riihijärvi works as a senior research scientist at the Department of Wireless Networks at RWTH Aachen University. Before joining RWTH he worked in a variety of research projects on wireless networks at VTT Electronics and at the Centre for Wireless Communications at University of Oulu. His research interests have lately been in applications of techniques from spatial statistics and stochastic geometry on characterization of wireless networks, embedded intelligence in general, use of metaheuristics in optimizing component-oriented systems, and various frequency assignment and topology control problems. He has also worked on various enabling technologies for cognitive wireless networks, including participating into the development of the Unified Link-Layer API as well as different localization and tracking frameworks. As a part of his research work he has participated extensively into international research projects as well as research projects carried out in collaboration with the industry.
Marina Petrova works as a chief research scientist at the Department of Wireless Networks at the RWTH Aachen University. She graduated in Electronics and Telecommunications engineering from the University of St. Cyril and Methodius, Skopje, Macedonia. Her research interests are focused on cognitive wireless networks, cognitive radios and adaptive wireless systems technologies. The topic of her Ph.D. thesis work at the RWTH Aachen has been also the multi-parameter optimization methods for cognitive radio networks. As part of her research work she has participated in the several international cooperative projects and industry projects in the field of wireless communications and cognitive radios. In Aachen she has also lead the research work that has been done towards the prototype implementation of gnu Radio based cognitive resource manager for cognitive radios. She has also served in technical program and organizing committees of conferences, among those IEEE DySPAN, IEEE Crowncom, the leading conferences in the field of cognitive radios and networks.Top
Challenges of Cognitive Radios in the physical layer
15 May 2008 (AM)
Prof. Aarne Mämmelä, VTT Technical Research Centre of Finland
Marja Matinmikko, VTT Technical Research Centre of Finland
This tutorial will emphasize system level aspects of cognitive radios from the physical layer point of view. A brief history and the state of the art of cognitive radios and the underlying spectrum regulatory framework will be given, some conceptual analysis will be made, and the major performance metrics will be covered. We will explore the challenges of cognitive radios including limited awareness (no “sense of sight”, finite probability of detection), hidden terminal problem, wide bandwidth (delays in sensing with existing components), emission to adjacent bands (spectral sidelobes, nonlinear properties), control bottleneck, and complexity. We will give examples of the challenges with an emphasis on the physical layer aspects and their effect on the cognitive radio system.
Aarne Mämmelä received the degree of Ph.D. (with distinction) from the University of Oulu in Finland in 1996 in the field of adaptive receivers in wireless telecommunications. From 1982 to 1993 he was with the University of Oulu. In 1993 he joined VTT Technical Research Centre of Finland in Oulu. Since 1996 he has been a research professor of digital signal processing in wireless telecommunications at VTT. Since 2000 he has also been an adjunct professor (docent) at the Helsinki University of Technology and in addition since 2004 at the University of Oulu. He is interested in system level aspects in cognitive radios and nonlinear phenomena, especially in the physical layer.
Marja Matinmikko was born in Rovaniemi, Finland, in 1979. She received her M.Sc. degree in industrial engineering and management, and Lic.Sc. degree in telecommunications from the University of Oulu, Oulu, Finland, in 2001 and 2007, respectively. She has been working at VTT Technical Research Centre of Finland in Oulu, Finland, since 2001 as a research scientist. She participated in the ITU-R standardization activities on the spectrum requirements of IMT-Advanced in preparation for the WRC-07, acted as the editor of Recommendation ITU-R M.1768 describing the spectrum requirement calculation methodology for IMT-Advanced, and authored several book chapters on the topic. Her current research interests include IMT-Advanced systems, cognitive radio networks and spectrum topics.Top
An Introduction to Cognitive Radio and Dynamic Spectrum Sharing
17 May 2008 (PM)
Prof. Friedrich K. Jondral, University of Karlsruhe (TH), Germany
Dr. Ivan Cosovic, NTT DoCoMo Euro-Labs, Germany
Dr. Gunther Auer, NTT DoCoMo Euro-Labs, Germany
Cognitive radio (CR) shows many facets. It has some awareness as well as some knowledge that is stored in data bases from where it may be retrieved when needed. Of course, the acquisition, the storage, the retrieval and the interpretation of knowledge are interesting processes. The engineer, however, is mainly interested how CRs can help to overcome transmission problems. The most prominent of these problems is to cope with the complicated mobile radio channels in order to make efficient use of the scarce frequency resources.
The first part of this tutorial discusses how CRs may be employed in dynamic spectrum sharing. Since CRs are built on software defined radios (SDRs), this technology is reviewed too from a commercial as well as from a military system’s view. A realistic projection of future CR applications in communications engineering is given.
The second part of this tutorial is mainly devoted to centralized spectrum trading approaches and design of MAC protocols in dynamic spectrum sharing system. Furthermore, views on the outcome of the World Radio Communication Conference 2007 (WRC-07) are given, and some European activities on spectrum sharing are presented.
Friedrich K. Jondral received the Dipl.-Math. and Dr.rer.nat. degrees in mathematics from the Technische Universität Braunschweig (Germany) in 1975 and 1979, respectively. During the winter semester 1977/78 he was a visiting scientist at the University of Nagoya (Japan). From 1979 to 1992 he was with AEG-Telefunken (now European Aeronautic Defence and Space Company, EADS), Ulm (Germany), where he held various research, development, and management positions. During this time he also lectured on courses in applied mathematics at the Universität Ulm where he was appointed Adjunct Professor in 1991. Since 1993 he has been full Professor and Head of the Institut für Nachrichtentechnik at the Universität Karlsruhe (TH), Germany.
Ivan Cosovic received the Dipl.-Ing. degree in electrical engineering from the University of Belgrade, Serbia, in 2001, and the Ph.D. in electrical engineering (with highest honors) from the Johannes Kepler University, Linz, Austria, in 2005. From 2002 to 2006, he was with the Institute of Communications and Navigation, German Aerospace Center (DLR), Wessling, Germany. He joined DoCoMo Euro-Labs, Munich, Germany, in 2006. He is a Guest Editor for the EURASIP Journal on Wireless Communications and Networking special issue on cognitive radio and dynamic spectrum sharing. He received DLR Science Award 2006 (DLR-Wissenschaftspreis 2006) of the German Aerospace Center. His research interests include spectrum sharing, cognitive radio and multi-carrier schemes for wireless communications systems.
Gunther Auer received the Dipl.-Ing. Degree in Electrical Engineering from Universität Ulm, Germany, in 1996, and the Ph.D. degree from the University of Edinburgh, UK, in 2000. From 2000 to 2001 he was a Research and Teaching Assistant with Universität Karlsruhe (TH), Germany. Since 2001 he is with NTT DoCoMo Euro-Labs, Munich, Germany. His research interests include self-organized networks and multi-carrier based communication systems, including medium access, cross-layer design, channel estimation and synchronization techniques.Top
Cognitive MIMO Mesh Network for Spectrum Sharing
17 May 2008 (PM)
Prof. Kei Sakaguchi, Tokyo Institute of Technology, Japan
Prof. Takeo Fujii, The University of Electro-Communications, Japan
Concept of cognitive radio is very wide from multi-mode systems to dynamic spectrum access with aggregating the plural spectrum sets for achieving high-speed and flexible wireless communications. As one of the key technologies for cognitive radio is a spectrum sharing. One practical spectrum sharing example is unlicensed wireless systems using 2.4GHz. In the conventional spectrum sharing system, only the simple carrier sense is a technique for mitigating the inter-system interference in the spectrum. To improve the spectrum efficiency and the flexibility of the communication over the existing wireless networks, multi-hop mesh networks are suitable. This is because multi-hop networks can keep minimizing giving interference toward the surrounding users by selecting the route and by controlling the power.
However, multi-hop networks increase the intra-spectrum interference due to share the spectrum their own nodes. In this tutorial, we focus on multi-hop mesh networks to mitigate the intra-system interference and inter-system interference for realizing the useful high-speed wireless communications over the existed primary systems. We have two main topics. First one is intra spectrum sharing by using MIMO mesh network. Second one is inter spectrum sharing by using MAC, routing and power control technologies on the secondary multi-hop networks under the existence of the primary system. By integrating these two topics, we can give you a novel secondary wireless distributed network concept overlaying primary wireless networks.
Kei Sakaguchi was born in Osaka, Japan, on November 27, 1973. He received the B.E. degree in electrical and computer engineering from Nagoya Institute of Technology, Japan, in 1996, the M.E. degree in information processing from Tokyo Institute of Technology, Japan, in 1998, and the Ph.D. degree in electrical and electronic engineering from Tokyo Institute of Technology in 2006. From 2000, he is an Assistant Professor at Tokyo Institute of Technology. He received the Young Engineer Awards from IEICE and IEEE AP-S Japan chapter in 2001 and 2002 respectively, and the Outstanding Paper Awards from SDR Forum and IEICE in 2004 and 2005 respectively. His current research interests are MIMO propagation measurements, MIMO communication systems, and software defined radio. He is a member of IEICE and IEEE.
Takeo Fujii received his B.E., M.E. and Ph.D. degrees in Electrical Engineering from Keio University, Yokohama, Japan, in 1997, 1999 and 2002, respectively. From 2000 to 2002, he was a research associate in the Department of Information and Computer Science, Keio University. From 2002 to 2006, he was an assistant professor in the Department of Electrical and Electronic Engineering, Tokyo University of Agriculture and Technology. Since 2006, he has been an associate professor in Advanced Wireless Communication Research Center (AWCC), The University of Electro-Communications. His current research interests are in broadband wireless communication systems and packet data wireless communication systems. He received Best Paper Award in IEEE VTC 1999-Fall, 2001 Active Research Award in Radio Communication Systems from IEICE technical committee on RCS, 2001 Ericsson Young Scientist Award and Young Researcher's Award from the IEICE in 2004. He is a member of IEICE and IEEE.Top
Cognitive Radio Networks – Opportunities, Challenges and Technologies for Dynamic Spectrum Access of TV Band White Spaces
17 May 2008 (PM)
Dr. Carlos Cordeiro, Intel Corporation, USA
Dr. Sai Shankar N, Broadcom Corporation, USA
Static spectrum allocation has resulted in low spectrum efficiency in licensed bands and poor performance of radio devices in crowded unlicensed bands. To overcome the above problem, we exploit the concept of spectral agility (a unique functionality of cognitive radio) such that radio devices can dynamically utilize idle spectral bands. Previously, the Federal Communication Commission (FCC) allocated frequency bands of the spectrum to a particular application, like TV, AM/FM radio systems, and cellular phone systems. The bands allocated to these applications are called licensed frequency bands. Consequently, existing solutions for wireless multimedia streaming concentrate on a single technology like wireless LAN or wireless PAN, Cellular, etc. However, it is expected that the necessary radio system resources will not be sufficient in the future, due to the limited radio spectrum in the current unlicensed frequency bands which are highly utilized by current consumer electronic devices. This motivates the need for CRs.
CRs have been receiving increasing attention in academia, industry, and government. What many people do not realize though is that early forms of CRs have been around us for years now, such as Transmit Power Control (TPC) and Dynamic Frequency Selection (DFS) defined for the 5GHz unlicensed band to avoid interference with radar signals. However, the difference between now and then is that the scope has been expanded to include dynamic reuse of other vacant licensed bands. Such is the case with the TV bands, where studies indicate that up to 90% of that spectrum is not utilized. As a consequence, regulatory bodies (e.g., the FCC in the USA, OFCOM in the UK, etc.) are considering the deployment of wireless technologies that can identify if a TV channel is available or not, and that would access a particular TV band without causing harmful interference to the TV service. CR technologies promise to enable efficient spectrum (re)use without causing harmful interference to incumbent users.
In this tutorial we look at various aspects related to the application, research and development of CRs in the particular case of TV bands, including architectures of cognitive radios, spectrum sensing, performance, protocols and algorithmic challenges. We will also cover ongoing industry activities in this area, including the IEEE 802.22 Working Group which is formulating the first worldwide standard for CR-based operation in vacant TV channels. This tutorial will also provide insights into future directions and evolution of this exciting field, and will review different open issues and research challenges that will hopefully catalyze new research efforts. We conclude the tutorial with a review of the aspects that need to be addressed to enable a smooth transition of various wireless multimedia applications to cognitive radio networks, and how the industry and academia have to evolve to meet the goal set by regulatory bodies as well as make CR techniques as true market-driven approaches.
Carlos Cordeiro is a Research Scientist in the Communications Technology Lab of Intel Corporation. Before joining Intel Labs, he worked for Philips Research North America and Nokia Research Center. Dr. Cordeiro has been involved with CRs for a number of years, which includes active participation in the IEEE 802.22 standardization effort as well as in building spectrum sensing and data communication CR prototypes for the TV bands. Due to his contributions to this area, he was selected by the IEEE as the worldwide 2007 New Face of Engineering and was the recipient of the IEEE Region 1’s 2007 Technological Innovation Award for “Pioneering Contributions to the Advancement and Design of Cognitive Radio based Wireless Technologies.” Dr. Cordeiro was also part of the team that received the 2007 Frost & Sullivan Excellence in Research of the Year Award in the field of cognitive networks. He is the co-founder and Industry Liaison to the IEEE ComSoc Technical Committee on Cognitive Networks and was the Guest Editor of the first IEEE J-SAC issue on CRs. He is the author of the textbook Ad Hoc and Sensor Networks: Theory and Applications published by World Scientific Publishing in early 2006. His interests include the IEEE 802 family of standards, cognitive radios, millimeter wave technologies, MIMO, and ad hoc and sensor networks. Dr. Cordeiro has served as Chair and TPC member of various meetings, has published over 75 papers in the wireless area alone, and holds numerous patents.
Sai Shankar N received his PhD degree from the department of Electrical Communication Engineering from Indian Institute of Science, Bangalore, India in the area of ATM networks. In 1998, He was awarded the German Fellowship, DAAD, in the department of mathematics, University of Kaiserslautern, Germany to work on queuing approaches in manufacturing. In 1999, he joined Philips Research, Eindhoven, the Netherlands, where he served as Research Scientist in the department of New Media Systems and Applications. He worked on various problems involving Hybrid, Fiber, Co-axial Cable (IEEE 802.14) Networks and IP protocols and provided efficient algorithms to improve protocol and buffer efficiency. In the year 2001 he joined Philips Research USA, Briarcliff Manor, NY as "Senior Member Research Staff" and worked actively in the area of WLANs and WPANs. He was the prime contributor of the wireless LAN standard in shaping QoS (TXOP, TSPEC, Admission Control and Simple Scheduler) related issues in the IEEE 802.11e Working Group that has been incorporated in IEEE 802.11e standard. He was also an active participant in the Ultra Wide Band (UWB) MAC working group of Multi-Band OFDM Alliance (MBOA) and is one of the prime contributor and author of the new MBOA MAC. To this end he was nominated as one of the five finalists by Electronic Engineering Times (EETimes) in the Innovator of the Year category in year 2005. Currently he is with Broadcom and works on issues related to next generation Bluetooth, milli-meter wave technologies, UWB, MIMO, Mesh Networking, Cognitive Radio, Viral communications and Cooperative networking. He also served as Adjunct Professor in Polytechnic University, Brooklyn teaching graduate course on Wireless Protocols. He is IEEE Standards Association voting member and Senior Member of IEEE and has served as Chair of many prestigious conferences and has authored more than 60 conference and journal papers, and has filed more than 60 patents.Top