Tutorials

Ultrawideband propagation channels

Presenter: Andreas F. Molisch

Abstract:

Like any other wireless communications systems, the performance of a UWB system is determined by the radio propagation channel between transmitter and receiver. There is an enormous amount of literature for narrowband wireless channels. However, those models cannot be easily generalized to UWB channels: there are many important basic differences in the propagation processes and the resulting models. In this talk, we will first give an overview of the basic differences between UWB and narrowband channels, followed by generic modeling methods for UWB channels. Special emphasis will be placed on the frequency dependence of the pathloss, non-WSSUS models, and changes in the small-scale fading statistics, as well as aspects of the power delay profile that are relevant for ranging. We then proceed to discuss the standardized channel models that have been developed for UWB, namely the IEEE 802.15.3a and the IEEE 802.15.4a models. We will describe the specifications, and also discuss the simplifications and possible pitfalls in the implementation and application of those models.

Presenter Biography:

Andy Molisch is a Distinguished Member of Technical Staff and Chief Wireless Standards Architect at Mitsubishi Electric Research Labs, and also Professor and Chair holder for Radio Systems at the Department of Electro- and Information Technology at Lund University, Sweden. His areas of interest are UWB, wireless propagation, MIMO, and cooperative communications. He has authored four books, eleven book chapters, some 110 journal papers, and numerous conference contributions, as well as more than 70 patents. He is active in standardization and has been chairman of several standardization organizations: IEEE 802.15.3a, IEEE 802.15.4a (chairman of channel modeling group), IEEE 802.11n, Multiband-OFDM alliance (chairman of scalability group), COST273 (chairman of the channel modeling group), and chairman of Commission C of URSI (International Union of Radio Science). Dr. Molisch is a Fellow of the IEEE, a Fellow of the IET, an IEEE Distinguished Lecturer, and recipient of several awards.

Ranging and Localization

Presenter: Davide Dardari, Andrea Giorgetti, and Dr. Andrea Conti WiLAB – Wireless Communications Laboratory

Abstract:

The ultrawide bandwidth (UWB) technology offers potential for achieving high positioning accuracy in cluttered environments (e.g., inside buildings where the Global Positioning System (GPS) is often inaccessible) due to its high time resolution and ability to penetrate obstacles. In this tutorial, the theoretical fundamental limits in ranging and active/passive localization based on the UWB technology as well as practical schemes will be explained. The main ranging/localization error sources will be illustrated. Some results derived from measured data in real environments will be shown to investigate the effect of system parameters on ranging and positioning accuracy.

Presenter Biography:

Davide Dardari received the Laurea degree in electronic engineering (summa cum laude) and the PhD degree in electronic engineering and computer science from the University of Bologna, Italy, in 1993 and 1998, respectively. In 1998, he joined the Dipartimento di Elettronica, Informatica e Sistemistica to develop his research activities in the area of digital communications. He has been involved in educational activities at the Engineering Faculty, University of Bologna, Italy, since 2000 dealing with Digital Communications and Electrical Communications. He has also played several important roles in various National and European Projects. Since 2005, he has been a Research Affiliate at Massachusetts Institute of Technology (MIT), Cambridge, USA. Now, he is an Associate Professor at the University of Bologna at Cesena, Italy, where he participates with WiLAB (Wireless Communications Laboratory). Recently, he has focused his activity on ultra-wide bandwidth (UWB) systems, ranging and localization techniques, as well as wireless sensor networks. He is an active member of the IEEE where he is the current secretary for the Radio Communications Committee of the IEEE Communication Society. He was co-chair of the Wireless Communications Symposium of the 2007 IEEE International Conference on Communications, and co-chair of the 2006 IEEE International Conference on Ultra-Wideband. He currently serves as an Editor for IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, Lead Editor for the EURASIP Journal on Advances in Signal Processing (Special Issue on Cooperative Localization in Wireless Ad Hoc and Sensor Networks) and Guest Editor for Proceedings of IEEE (Special Issue on UWB Technology & Emerging Applications). He also serves as a reviewer for Transactions/Journals and Conferences, and as a TPC member for numerous international conferences.

Andrea Giorgetti received the Dr. Ing. degree (magna cum laude) in electronic engineering and the Ph.D. degree in electronic engineering and computer science, both from the University of Bologna, Bologna, Italy, in 1999 and 2003, respectively. Since 2003, he has been with the Istituto di Elettronica e di Ingegneria dell'Informazione e delle Telecomunicazioni (IEIIT), Research Unit at Bologna of the National Research Council (CNR), Bologna, Italy. In 2005 he has been a Researcher of the National Research Council, and since 2006 he is Assistant Professor at the II Engineering Faculty, University of Bologna, where he joined the Department of Electronics, Computer Sciences and Systems (DEIS). Since the spring 2006 he is Research Affiliate at the Laboratory for Information and Decision Systems (LIDS), Massachusetts Institute of Technology (MIT), Cambridge, USA, working on the ultrawide bandwidth technology. His research interests include ultrawide bandwidth communications systems, wireless sensor networks, and multiple-antenna systems. He served on the Technical Program Committees for the IEEE Int. Conf. on Communications (ICC 2005), the Int. Workshop on UWB Technologies (IWUWBT 2005), the IEEE Int. Conf. on Ultra Wideband (ICUWB 2006) and the IEEE Int. Conf. on Communications (ICC 2007). He is Co-Chair of the Wireless Networking Symposium at the IEEE Int. Conf. on Communications (ICC 2008), Beijing, CHINA, May 2008.

Andrea Conti received the Dr .Ing. degree (with honors) in telecommunications engineering and the Ph.D. degree in electronic engineering and computer science in 1997 and 2001, respectively, from the University of Bologna, Bologna, Italy. From 1999 to 2002, he was with the Consorzio Nazionale Interuniversitario per le Telecomunicazioni (CNIT) at the University of Bologna, and from November 2002, he joined the Istituto di Elettronica e di Ingegneria dell’Informazione e delle Telecomunicazioni of the National Research Council, Research Unit of Bologna (IEIIT-BO/CNR). In July 2005, he joined the University of Ferrara, Ferrara, Italy, where he is currently an Assistant Professor. In the summer of 2001, he joined the Wireless Section of AT&T Research Laboratories, Middletown, NJ, working on the performance of digital telecommunication systems with diversity reception. From February 2003, he visited the Laboratory for Information and Decision Systems (LIDS), Massachusetts Institute of Technology, Cambridge, working on the performance of adaptive and nonadaptive multilevel quadratic amplitude modulation (M-QAM) in faded multichannel reception and localization techniques. He is research affiliate with WiLAB, IEIIT-BO/CNR, CNIT, and Wireless Communications Group at LIDS, MIT.

His actual research interests are in the area of wireless communications including localization, adaptive transmission and multi-channel reception, coding in faded multiple-input multiple-output channels, wireless cooperative networks, wireless sensor networks, and cooperative distributed telemeasurement laboratories.

He is Editor for IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, Lead Editor for the EURASIP Journal on Advances in Signal Processing (Special Issue on Wireless Cooperative Networks), and served as Reviewer and TPC member for various IEEE Transactions/Journals and Conferences. He is co-author of the book “Wireless Sensor and Actuator Networks: enabling technologies, information processing and protocol design”, Elsevier, 2008.