Wireless LANs Systems: An Advanced Resource Assignement Algorithm

The paper describes the design and simulation of a radio modem architecture, which provides wireless access to Internet in a single-hop, ad hoc network.The main emphasis is on the Medium Access Control (MAC) and Dynamic Link Control (DLC) layer’s design, and in particular on the adopted innovative scheduling algorithm, which has been developed to satisfy the system requirements of the WIND-FLEX radio modem. The algorithm is presented and compared to the Earliest Deadline First (EDF) solution.Several software simulation tests have been executed on the network, to test the performance of the system, in order to verify the capability of the scheduler algorithm to satisfy the expected requirements and the efficiency of the implemented solutions. Giuseppe Razzano was born in Roma, Italy, in 1974. He has graduated in Electronic Engineering “summa cum laude” and has received PhD in Communication Systems and Computer Science, in 2004 from University of Rome “La Sapienza”. From 2000 to 2001 he worked as research assistant at VTT electronics, in Finland. From 2004 to 2005 he worked as senior researcher at Forschungzentrum Telekommunikation Wien (Telecommunication Research Centre Vienna) in Austria. Currently, he works as System Engineer for Vitrociset S.p.A., working in a project funded by European Space Agency (ESA), for the development of a new generation space launcher vehicle (VEGA). In the past years, he worked in several projects funded by EC within the IST (Information Societies Technology) program, being also involved in projects in collaboration with Italian companies. His research is focused on resource management algorithms for wireless LANs and cellular networks. He is also interested in object-oriented programming and development methodologies. In these fields, he is author of several papers published in international journals and conferences. Francesco Delli Priscoli was born in Rome in 1962. He graduated in Electronic Engineering “summa cum laude” from the University of Rome “La Sapienza” in 1986. He received the Ph.D. in system engineering from the University of Rome “La Sapienza” in 1991. From 1986 to 1991 he worked in the “Studies and Experimentation” Department of Telespazio (Rome). Since 1991 he is working for the University of Rome “La Sapienza” where, at present, he is “Full Professor” and holds the courses “Automatic Controls”, “System Theory” and “Network Control and Management I and II”. In the framework of his activity, he researches in the nonlinear control theory and in the area of control-based resource management procedures for the third and forth generation of mobile systems. He is the author of about 150 technical papers on the above topics appeared on major international reviews (about 50) and conferences (about 100). In 2000 he has been scientific consultant for the Italian Council of Ministers in the framework of the auction for the assignment of the Italian Universal Mobile Telecommunication System (UMTS) licensees. He is an associate editor of Control Engineering Practice and a member of the IFAC Technical Committee on “Networked Systems”. He is/has been scientific responsible, for the University of Rome “La Sapienza”, of 17 projects financed by the European Union (fourth, fifth and sixth framework programmes) or by the European Space Agency (ESA), dealing with resource management for UMTS and broadband terrestrial and satellite wireless systems. He is also a project evaluator for the European Commission. Roberto Cusani received the “laurea” degree in Electronic Engineering (cum laude) and the Ph.D. in Communication Systems and Computer Science from the University of Rome “La Sapienza”. From 1986 to 1990 he was research engineer at the University of Rome “Tor Vergata”, teaching Digital Signal Processing. In 1991 he joined the University of Rome “La Sapienza” as Associate Professor of Signal Theory. In 2000 he becomes Full Professor and teaches Information Theory and Coding, and Mobile Communications. His former research activities concern transmission and coding of signals and images, with emphasis on random processes, spectral estimation and image coding. Since 1992 he focused his activities in the field of the digital communication systems, with emphasis on channel equalisation and coding for HF and radio-mobile (GSM) links, on the design of CDMA receivers for UMTS and, in general, on the use of digital techniques within telecommunication equipments. More recently his interests also includes the study of MAC (Multiple Access Control) protocols with application to wireless area networks (WLANs), reconfigurable ad-hoc networks and satellite links. He is author of more than 100 publications in international journals and conferences, of the text-book “Teoria dei Segnali” and of five patents regarding telecommunication applications. He was involved in many research programs, both national and international, and in projects with the industrie.     

Access points vulnerabilities to DoS attacks in 802.11 networks

We describe possible denial of service attacks to access points in infrastructure wireless networks using the 802.11b protocol. To carry out such attacks, only commodity hardware and software components are required. The experimental results obtained on a large set of different access points show that serious vulnerabilities exist in any device we tested and that a single malicious station can easily hinder any legitimate communication within a basic service set. Francesco Ferreri graduated in Software Engineering in 2004 at Rome University “Tor Vergata”. He then joined CASPUR (Italian Interuniversities Consortium for Supercomputing Applications) where he led research activities involving wireless networks and IPv6 integration. He’s currently employed at NaMeX, Rome’s Internet Exchange Point, as a network and systems engineer. Leonardo Valcamonici graduated in Maths in 1994 at “La Sapienza” University in Rome. After that he joined CASPUR (Italian Interuniversities Consortium for Supercomputing Applications) where, in the beginning, he was involved in research activities in the field of parallel and distributed computing. After that he became a network and security engineer. He is now CASPUR’s Information Systems Security Officer and Network Applications and Services Team Leader.” Massimo Bernaschi graduated in physics in 1987 at “Tor Vergata” University in Rome. After that he joined the IBM European Center for Scientific and Engineering Computing (ECSEC) in Rome. He spent ten years with IBM working in the field of parallel and distributed computing. Currently he is with the Italian National Research Council (CNR) as chief technology officer of the Institute for Computing Applications. Moreover, he is an adjunct professor of Computer Science in “La Sapienza” University in Rome.     

Programmable CNN Analogue Chip for RD-PDE Multi-Method Simulations

Cellular Non Linear Networks can be useful applied for the solution of several types of Partial Differential Equations (PDEs). This paper will describe an analogue circuit implementation for the simulation of one-dimensional Reaction-Diffusion PDE with the possibility to set different boundary conditions as well as to select different discretization methodologies. Fausto Sargeni was born in Riano (ROMA) in 1961. He received the Dipl. Eng. degree in Electronic Engineering at the University of Rome “La Sapienza" in 1987. In 1989 he jointed the Dept. of Electronic Engineering at the University of Rome “Tor Vergata" as Assistant Professor. In 1998 he became Associate Professor. His research interests include analog VLSI circuits for non linear circuits and high-speed interconnections. Vincenzo Bonaiuto was born in Rome, Italy, in 1962. He received the Dipl. Eng. degree in Electronic Engineering at the University of Rome “La Sapienza". In 1997 he received the the Ph.D. in Telecommunication and Microelectronics. In 1996 he jointed the Electronic Engineering Dept. as Assistant Professor at the University of Rome “Tor Vergata” and, in 2002, he became Associate Professor. His main research interests are in the area of non linear circuits, Artificial Neural Networks analogue/digital VLSI circuits implementation.     

Input-Matching and Offset-Cancelling Networks for Limiting Amplifiers in Optical Communication Systems

The diffusion of optical communication systems in the access network and for short-haul datacom applications requires the use of low-cost plastic packages: the functional block most affected is the limiting amplifier, that is often the first stage of the Clock and Data Recovery (CDR) IC. In this paper we illustrate the design issues of the input-matching and offset-cancelling network for a differential limiting amplifier for optical communication systems, with particular emphasis on the effect of bond wires. We discuss the limitations of passive feedback networks when used both for offset suppression and for input matching, and propose a topology that overcomes such limitations by using an active feedback loop. A 50 Ω-loaded differential pair is used to achieve input matching and high offset suppression, and its buffering action desensitizes the input matching from the effect of the bond wires connecting off-chip filtering capacitors. Very good performance even with low cost plastic packages can be achieved by solving the trade-off between power consumption, offset suppression and the value of the low-pass filtering capacitors. Design examples of CDR IC's for 2.5 Gb/s optical systems are presented to compare the proposed topology with solutions based on passive feedback networks. Marco Balsi received the laurea (M.Sc.) degree in 1991 and the dottorato di ricerca (Ph.D.) in 1995 in Electronic Engineering from University of Roma “La Sapienza”, Roma, Italy. Since 1996 he is with “La Sapienza” University as ricercatore (assistant professor). He is engaged in research in nonlinear and soft-computing-based signal processing (especially for biomedical imaging), artificial vision, mechatronics, and anti-personnel mine detection. He has published about 60 paper in international journals and refereed conferences. Francesco Centurelli received the laurea degree (cum laude) and the Ph.D. degree in electronic engineering from the University of Roma “La Sapienza”, Roma, Italy, in 1995 and 2000, respectively. He is currently doing postdoctoral work with the Electronic Engineering Department of the University of Roma “La Sapienza.” His research interests include system-level analysis and design of clock recovery circuits and high-speed analog integrated circuits, with particular emphasis on gigabit-rate optical communication systems. Andrea Pallotta received the M.S. degree in electronic engineering from the University of Ancona, Ancona, Italy. From 1991 to 1999, he was with Italtel, Italy, where he joined several European Community research projects in the field of SDH and WDM fiber-optic transmission systems for both transport and access networks. From 1999 to 2000, he was with Siemens Information and Communication Networks, where he was responsible for the SDH Cross-Connect advanced development group. In September 2000, he joined the STMicroelectronics Company, where he is currently responsible for the electrooptical interface design group. His research interests include GaAs and silicon high-speed ICs, active optical devices, high-speed TX and RX optical modules, and fiber-optic transmission system engineering. Alessandro Trifiletti was born in Roma, Italy, in 1959. In 1991, he joined the Electronic Engineering Department of the University of Roma “La Sapienza” as a Research Assistant and is currently an Assistant Professor. His research interests include high-speed circuit design techniques and III-V device modeling.     

Energy efficient node-to-node authentication and communication confidentiality in wireless sensor networks

A distributed Wireless Sensor Network (WSN) is a collection of low-end devices with wireless message exchange capabilities. Due to the scarcity of hardware resources, the lack of network infrastructures, and the threats to security, implementing secure pair-wise communications among any pair of sensors is a challenging problem in distributed WSNs. In particular, memory and energy consumption as well as resilience to sensor physical compromise are the most stringent requirements. In this paper, we introduce a new threat model to communications confidentiality in WSNs, the smart attacker model. Under this new, more realistic model, the security features of previously proposed schemes decrease drastically. We then describe a novel pseudo-random key pre-deployment strategy ESP that combines all the following properties: (a) it supports an energy-efficient key discovery phase requiring no communications; (b) it provides node to node authentication; (c) it is highly resistant to the smart attacker.We provide both asymptotic results and extensive simulations of the schemes that are beingproposed. This work was partially funded by the WEB-MINDS project supported by the Italian MIUR under the FIRB program, and by the PRIN 2003 “Web-based Management and Representation of Spatial and Geographic Data” program from the Italian MIUR. Roberto Di Pietro is partially funded by ISTI-CNR, WNLab, Pisa, with a Post-doc grant under the IS-MANET program. Roberto Di Pietro received the Ph.D. in Computer Science from the University of Roma “La Sapienza”, Italy, in 2004. He received the Bs. and Ms. degree in Computer Science from the University of Pisa, Italy, in 1994. Since 1995 he has been working for the technical branch of the Italian Army and the Internal Affairs Ministry. His main research interests include: security for mobile ad hoc and wireless networks, security for distributed systems, secure multicast, applied cryptography and computer forensics. Luigi V. Mancini received the PhD degre in Computer Science from the University of Newcastle upon Tyne, UK, in 1989, and the Laurea degree in Computer Science from the University of Pisa, Italy, in 1983. From 2000, he is a full professor of Computer Science at the Dipartimento di Informatica of the University of Rome “La Sapienza”. Since 1994, he is a visiting research professor of the Center for Secure Information Systems, GMU, Virginia, USA. Currently he is the advisor of six Ph.D students. His current research interests include: computer network and information security, wireless network security, fault-tolerant distributed systems, large-scale peer-to-peer systems, and hard-real-time distributed systems. He published more than 60 scientific papers in international conferences and journals such as: ACM TISSEC, IEEE TKDE, IEEE TPDS, and IEEE TSE. He served in the program committees of several international conferences which include: ACM Conference on Computer and Communication Security, ACM Conference on Conceptual Modeling, ACM Symposium on Access Control Models and Technology, ACM Workshop of Security of Ad-hoc and Sensor Networks, IEEE Securecomm, IEEE Conference on Cluster Computing. He is also the program chair of the first two editions of the IEEE Workshop on Hot Topics in Peer-to-Peer Systems held in 2004 (Volendam, Holand) and in 2005 (San Diego, California). Currently, he is a member of the Scientific Board of the Italian Communication Police force, and the director of the Master degree program in Computer and Network Security of the University of Rome “La Sapienza”, Italy. Alessandro Mei received the Laurea degree in computer science from the University of Pisa, Italy, in 1994, and the PhD degree in mathematics from the University of Trento, Italy, in 1999. In 1998, he was at the Department of EE-Systems of the University of Southern California, Los Angeles, as a visiting scholar for one year. After holding a postdoctoral position at the University of Trento, in 2001 he joined the Faculty of Science of the University of Rome "La Sapienza", Italy, as an assistant professor of computer science. His main research interests include security of distributed systems and networks, algorithms for parallel, distributed, and optical systems and reconfigurable computing. He was presented with the Best Paper Award of the 16th IEEE International Parallel and Distributed Processing Symposium in 2002, the EE-Systems Outstanding Research Paper Award of the University of Southern California for 2000, and the Outstanding Paper Award of the Fifth IEEE/ACM International Conference on High Performance Computing in 1998. He is a member of the ACM and the IEEE and, from 2005, he is an Associate Editor of IEEE Transactions on Computers.     

Controlled sink mobility for prolonging wireless sensor networks lifetime

This paper demonstrates the advantages of using controlled mobility in wireless sensor networks (WSNs) for increasing their lifetime, i.e., the period of time the network is able to provide its intended functionalities. More specifically, for WSNs that comprise a large number of statically placed sensor nodes transmitting data to a collection point (the sink), we show that by controlling the sink movements we can obtain remarkable lifetime improvements. In order to determine sink movements, we first define a Mixed Integer Linear Programming (MILP) analytical model whose solution determines those sink routes that maximize network lifetime. Our contribution expands further by defining the first heuristics for controlled sink movements that are fully distributed and localized. Our Greedy Maximum Residual Energy (GMRE) heuristic moves the sink from its current location to a new site as if drawn toward the area where nodes have the highest residual energy. We also introduce a simple distributed mobility scheme (Random Movement or RM) according to which the sink moves uncontrolled and randomly throughout the network. The different mobility schemes are compared through extensive ns2-based simulations in networks with different nodes deployment, data routing protocols, and constraints on the sink movements. In all considered scenarios, we observe that moving the sink always increases network lifetime. In particular, our experiments show that controlling the mobility of the sink leads to remarkable improvements, which are as high as sixfold compared to having the sink statically (and optimally) placed, and as high as twofold compared to uncontrolled mobility. Stefano Basagni holds a Ph.D. in electrical engineering from the University of Texas at Dallas (December 2001) and a Ph.D. in computer science from the University of Milano, Italy (May 1998). He received his B.Sc. degree in computer science from the University of Pisa, Italy, in 1991. Since Winter 2002 he is on faculty at the Department of Electrical and Computer Engineering at Northeastern University, in Boston, MA. From August 2000 to January 2002 he was professor of computer science at the Department of Computer Science of the Erik Jonsson School of Engineering and Computer Science, The University of Texas at Dallas. Dr. Basagni’s current research interests concern research and implementation aspects of mobile networks and wireless communications systems, Bluetooth and sensor networking, definition and performance evaluation of network protocols and theoretical and practical aspects of distributed algorithms. Dr. Basagni has published over four dozens of referred technical papers and book chapters. He is also co-editor of two books. Dr. Basagni served as a guest editor of the special issue of the Journal on Special Topics in Mobile Networking and Applications (MONET) on Multipoint Communication in Wireless Mobile Networks, of the special issue on mobile ad hoc networks of the Wiley’s Interscience’s Wireless Communications & Mobile Networks journal, and of the Elsevier’s journal Algorithmica on algorithmic aspects of mobile computing and communications. Dr. Basagni serves as a member of the editorial board and of the technical program committee of ACM and IEEE journals and international conferences. He is a senior member of the ACM (including the ACM SIGMOBILE), senior member of the IEEE (Computer and Communication societies), and member of ASEE (American Society for Engineering Education). Alessio Carosi received the M.S. degree “summa cum laude” in Computer Science in 2004 from Rome University “La Sapienza.” He is currently a Ph.D. candidate in Computer Science at Rome University “La Sapienza.” His research interests include protocols for ad hoc and sensor networks, underwater systems and delay tolerant networking. Emanuel Melachrinoudis received the Ph.D. degree in industrial engineering and operations research from the University of Massachusetts, Amherst, MA. He is currently the Director of Industrial Engineering and Associate Chairman of the Department of Mechanical and Industrial Engineering at Northeastern University, Boston, MA. His research interests are in the areas of network optimization and multiple criteria optimization with applications to telecommunication networks, distribution networks, location and routing. He is a member of the Editorial Board of the International Journal of Operational Research. He has published in journals such as Management Science, Transportation Science, Networks, European Journal of Operational Research, Naval Research Logistics and IIE Transactions. Chiara Petrioli received the Laurea degree “summa cum laude” in computer science in 1993, and the Ph.D. degree in computer engineering in 1998, both from Rome University “La Sapienza,” Italy. She is currently Associate Professor with the Computer Science Department at Rome University “La Sapienza.” Her current work focuses on ad hoc and sensor networks, Delay Tolerant Networks, Personal Area Networks, Energy-conserving protocols, QoS in IP networks and Content Delivery Networks where she contributed around sixty papers published in prominent international journals and conferences. Prior to Rome University she was research associate at Politecnico di Milano and was working with the Italian Space agency (ASI) and Alenia Spazio. Dr. Petrioli was guest editor of the special issue on “Energy-conserving protocols in wireless Networks” of the ACM/Kluwer Journal on Special Topics in Mobile Networking and Applications (ACM MONET) and is associate editor of IEEE Transactions on Vehicular Technology, the ACM/Kluwer Wireless Networks journal, the Wiley InterScience Wireless Communications & Mobile Computing journal and the Elsevier Ad Hoc Networks journal. She has served in the organizing committee and technical program committee of several leading conferences in the area of networking and mobile computing including ACM Mobicom, ACM Mobihoc, IEEE ICC,IEEE Globecom. She is member of the steering committee of ACM Sensys and of the international conference on Mobile and Ubiquitous Systems: Networking and Services (Mobiquitous) and serves as member of the ACM SIGMOBILE executive committee. Dr. Petrioli was a Fulbright scholar. She is a senior member of IEEE and a member of ACM. Z. Maria Wang received her Bachelor degree in Electrical Engineering with the highest honor from Beijing Institute of Light Industry in China, her M.S. degree in Industrial Engineering/Operations Research from Dalhousie University, Canada and her Ph.D. in Industrial Engineering/Operations Research from Northeastern University, Boston. She served as a R&D Analyst for General Dynamics. Currently MS. Wang serves as an Optimization Analyst with Nomis Solutions, Inc.     

Tightening the upper bound for the minimum energy broadcasting

In this paper we present a new upper bound on the approximation ratio of the Minimum Spanning Tree heuristic for the basic problem on Ad-Hoc Networks given by the Minimum Energy Broadcast Routing (MEBR). We introduce a new analysis allowing to establish a 6.33-approximation ratio in the 2-dimensional case, thus decreasing the previously known 7.6 upper bound [4], almost closing the gap with the lower bound of 6 [12]. Preliminary results concerning this paper appeared in [9]. Michele Flammini received the degree in Computer Science at the University of L’Aquila in 1990 and the Ph.D. degree in Computer Science at the University of Rome “La Sapienza” in 1995. He is full professor at the Computer Science Department of the University of L’Aquila since March 2005. His research interests include algorithms and computational complexity, game theory, communication problems in interconnection networks and routing. He has authored and co-authored more than 70 papers in his fields of interest published in the most reputed international conferences and journals. Ralf Klasing received the PhD degree from the University of Paderborn in 1995. From 1995 to 1997, he was an Assistant Professor at the University of Kiel. From 1997 to 1998, he was a Research Fellow at the University of Warwick. From 1998 to 2000, he was an Assistant Professor at RWTH Aachen. From 2000 to 2002, he was a Lecturer at King’s College London. In 2002, he joined the CNRS as a permanent researcher. From 2002 to 2005, he was affiliated to the laboratory I3S in Sophia Antipolis. Currently, he is affiliated to the laboratory LaBRI in Bordeaux. He has co-authored a Springer Monograph, a book chapter, and has published more than 40 papers in refereed international periodicals. His research interests include Communication Algorithms in Networks, Approximation Algorithms for Combinatorially Hard Problems, Web Graphs and Web Algorithms, and Optimization Problems in Ad-Hoc Wireless Networks. Alfredo Navarra received the degree in Computer Science at the University of L’Aquila in 2000 and the Ph.D. degree in Computer Science at the University of Rome “La Sapienza” in 2004. From 2003 to 2004, he joined the MASCOTTE project team at the INRIA institute of Sophia Antipolis as PhD student and PostDoc for almost two years. In 2005, he was a temporary researcher at the University of L’Aquila. In 2006, he joined the laboratory LaBRI in Bordeaux as PostDoc. His research interests include, algorithms and computational complexity, communication, modelling as well as analysis and experimentation problems on protocols and routing algorithms for interconnaction networks such as Ad Hoc, Wireless, Mobile and Sensor Networks. He has authored and co-authored more than 25 papers in his fields of interest published in the most reputed international conferences and journals. Stéphane Pérennes is a permanent researcher of the French Centre National de la Recherche Scientifique (CNRS). He is affiliated to the MASCOTTE project team at the Institut National de Recherche en Informatique et Automatique (INRIA) of Sophia Antipolis. He has authored and co-authored more than 70 papers in his fields of interest that vary from pure theoretical to applied issues on algorithms and complexity, networking and routing.     

Providing Throughput Guarantees in 802.11e WLAN Through a Dynamic Priority Assignment Mechanism

Supporting real-time and interactive traffic in addition to traditional data traffic with a best-effort nature represents a constantly rising need in any kind of telecommunications environment. The IEEE 802.11 based WLAN (Wireless Local Area Network) environment does not represent an exception. This is why at different protocol layers, and primarily at the MAC layer, many efforts are being put by both the research community and the standardization bodies to design effective mechanisms for user QoS (Quality of Service) differentiation. Although early results are coming into sight, such as, for example, the IEEE 802.11e standard release, still a thorough research activity is required. Aim of the present paper is to contribute to the cited research issue by proposing an improvement to the “static” traffic prioritisation mechanism foreseen by the IEEE 802.11e MAC (Medium Access Control) protocol. This latter shows a twofold drawback. First, there is no certainty that QoS requirements relevant to a given application are always fulfilled by the “statically” associated priority. Second, resource requests of the applications are not adapted to the (usually highly) variable traffic conditions of a distributed WLAN environment. The algorithm we propose is specifically tailored to “dynamically” assign 802.11e MAC priorities, depending on both application QoS requirements and observed network congestion conditions. It is carefully designed, implemented into a system simulation tool, and its highly effective behaviour assessed under variable traffic and system conditions. Antonio Iera graduated in Computer Engineering at the University of Calabria, Italy, in 1991 and received a Master Diploma in Information Technology from CEFRIEL/Politecnico di Milano, Italy, in 1992 and a Ph.D. degree from the University of Calabria, Italy, in 1996. From 1994 to 1995 he has been at the Mobile Network Division Research Center, Siemens AG Muenchen, Germany to participate to the CEC Project “RACE II 2084 ATDMA (Advanced TDMA Mobile Access)” under a “Commission of European Communities Fellowship Contract in RACE Mobility Action”. He has been with the University of Reggio Calabria, Italy, from 1997 to 2000 as Assistant Professor, and from 2001 to 2005 as Associate Professor. Currently, he is Full Professor of Telecommunications at the same University. In 1995 and in 1996 he has been the recipient of an IEEE Paper Award for the papers presented at the IEEE International Conference on Universal Personal Communications ICUPC'95, and an IEICE/IEEE Outstanding Paper Award for the paper presented at the IEEE ATM Workshop'99, respectively. He served as member of Technical Program Committees of several International Conferences, and in 2003 he has been co-Guest Editor for the special issue “QoS in Next-generation Wireless Multimedia Communications Systems” in the IEEE Wireless Communications Magazine. His research interests include QoS control and resource management in Personal Communications Systems and Enhanced Wireless and Satellite Systems. Giuseppe Ruggeri received the degree in electronics engineering from the University of Catania, Italy, in 1998. He received the Ph.D. degree in electronics, computer science and telecommunications engineering with a dissertation on “Advanced Methods to Improve the QoS in VoIP Systems Based on VBR Speech Coders”. His interests include the field of adaptive-rate voice transmission for IP Telephony applications, and support of Quality of Service in heterogeneous wireless networks and WLAN-3G interconnection-integration . He is currently Assistant Professor in the Department of Computer Science, Mathematics, Electronic and transportation systems (DIMET) at the University “Mediterranea” of Reggio Calabria. His mail address is ruggeri@ing.unirc.it. Domenico Tripodi received M.S. degree (cum laude) in electronic engeneering from the University ‘Mediterranea' of Reggio Calabria, Italy in 2003. He won a post-degree scholarship from CNIT in 2004, and he is currently at CNIT Research Unit of Reggio Calabria. His reasearch interest are in the area of QoS provisioning in Mobile Ad-Hoc Networks.     

Introducing consciousness in UWB networks by hybrid modelling of admission control

We formalize a model for a self-organizing network of nodes that operate according to the UWB principle based on hybrid modelling formalism. We design the rules that lead to the formation of the network and in particular an admission control procedure that is capable to handle both continuous and discrete perturbations, while maintaining the network in a condition of stability. Cognition is introduced in the model by allowing nodes to adjust their rules of operation based on the perception of the environment by an elected node, serving as the observer, that is aware of context, evaluates, and selects one strategy of operation. Maria-Gabriella Di Benedetto obtained her Ph.D. in Telecommunications in 1987 from the University of Rome La Sapienza, Italy. In 1991, she joined the Faculty of Engineering of University of Rome La Sapienza, where currently she is a Full Professor of Telecommunications at the Infocom Department. She has held visiting positions at the Massachusetts Institute of Technology, the University of California, Berkeley, and the University of Paris XI, France. In 1994, she received the Mac Kay Professorship award from the University of California, Berkeley. Her research interests include wireless communication systems and speech science. From 1995 to 2000, she directed four European projects for the design of UMTS. Since 2000, she has been active in fostering the development of Ultra Wide Band (UWB) radio communications in Europe. Within the 5th framework, she directed for the Infocom Dept. two European projects (whyless.com and UCAN) aimed at the design and implementation of UWB ad-hoc networks. Currently, within the 6th EU Framework, her “Networking with UWB” research group participates in the PULSERS Integrated Project which will integrate UWB research and development in Europe for the next years, and in the LIAISON Integrated Project as regards the application of UWB to location-based services. She also participates in the HYCON network of excellence. Dr. Di Benedetto has co-edited several Special Issues on UWB communications and networks for several Journals including IEEE JSAC, Journal of Communications and Networks, Mobile Networks and Applications, Eurasip. In 2004, Dr. Di Benedetto co-authored with G. Giancola the first published book on UWB for communications titled “Understanding Ultra Wide Band Radio Fundamentals” and published by Prentice Hall. She recently completed the co-edition of two new books on UWB that will be published by 2005: UWB Communication Systems—A comprehensive overview, with T. Kaiser, D. Porcino, A. Molisch, and I. Oppermann, Hindawi Publishing Corporation, 2005, and Ultra Wideband Wireless Communications with H. Arslan and Z.N. Chen, John Wiley & Sons, Inc., 2005. Maria Domenica Di Benedetto obtained the “Dr. Ing.” degree (summa cum laude) of Electrical Engineering and Computer Science, University of Roma “La Sapienza” in 1976 (Mosè Ascoli Best Student Award). In 1981, she obtained the degree “Docteur-Ingénieur” and in 1987 the degree “Doctorat d’Etat ès Sciences”, Université de Paris-Sud, Orsay, France. From 1979 to 1983, she had been Research Engineer at the scientific centers of IBM in Paris and Rome. From 1983 to 1987, she had been Assistant Professor at the University of Roma “La Sapienza”. From 1987 to 1990, she had been Associate Professor at the Istituto Universitario Navale of Naples. From 1990 to 1993, had been Associate Professor at the University of Roma “La Sapienza”. Since 1994, she has been Professor of Control Theory at University of L’Aquila. From 1995 to 2002, she was Adjunct Professor, Department of EECS, University of California at Berkeley. In 1987, she was Visiting Scientist at MIT; in 1988, 1989 and 1992, Visiting Professor at the University of Michigan, Ann Arbor; in 1992, Chercheur Associé, C.N.R.S., Poste Rouge, Ecole Nationale Supérieure de Mécanique, Nantes, France; in 1990, 1992, 1994 and 1995, McKay Professor at the University of California at Berkeley. Her research interests revolve around nonlinear control and hybrid systems. She was Associate Editor of the IEEE Transactions of Automatic Control and has been Subject Editor of the International Journal of Robust and Nonlinear Control since 1995. Since 2005, she has been a member of the IFAC Technical Committee on Discrete Event and Hybrid Systems. Since 2000, she has been the Director of the Center of Excellence for Research DEWS on “Architectures and Design methodologies for Embedded controllers, Wireless interconnect and System-on-chip”, University of L’Aquila. She is IEEE Fellow and Chairperson of the Standing Committee on Fellow Nominations, IEEE Control Systems Society. Guerino Giancola received the “Laurea” degree (magna cum laude) in Telecommunications Engineering, and the Ph.D. degree in Information and Communication Engineering from University of Rome La Sapienza, in 2001 and 2005, respectively. He is currently a research affiliate at the INFOCOM Department at University of Rome La Sapienza, where is actually holding the course of “Electrical Communications” for the degree on Electronic Engineering. His research interests include the analysis and modelling of Multi User Interference in Impulse Radio systems, and the design of Medium Access Control functions and protocols for UWB ad-hoc networks. Guerino Giancola recently co-authored with Prof. Maria-Gabriella Di Benedetto a book on Ultra Wide Band from radio to the network, titled “Understanding Ultra Wide Band Radio Fundamentals” and published by Prentice Hall in June 2004. He is now involved in the European project “PULSERS—Pervasive Ultra wideband Low Spectral Energy Radio Systems” and in the European Network of Excellence “HYCON—Hybrid Control: Taming Heterogeneity and Complexity of Networked Embedded Systems”. Guerino Giancola is a member of the IEEE Communication Society.     

MPARM: Exploring the Multi-Processor SoC Design Space with SystemC

Technology is making the integration of a large number of processors on the same silicon die technically feasible. These multi-processor systems-on-chip (MP-SoC) can provide a high degree of flexibility and represent the most efficient architectural solution for supporting multimedia applications, characterized by the request for highly parallel computation. As a consequence, tools for the simulation of these systems are needed for the design stage, with the distinctive requirement of simulation speed, accuracy and capability to support design space exploration. We developed a complete simulation platform for a MP-SoC called MP-ARM, based on SystemC as modelling and simulation environment, and including models for processors, the AMBA bus compliant communication architecture, memory models and support for parallel programming. A fully operating linux version for embedded systems has been ported on this platform, and a cross-toolchain has been developed as well. Our MP simulation environment turns out to be a powerful tool for the MP-SOC design stage. As an example thereof, we use our tool to evaluate the impact on system performance of architectural parameters and of bus arbitration policies, showing that the effectiveness of a particular system configuration strongly depends on the application domain and the generated traffic profile.Luca Benini received the B.S. degree (summa cum laude) in electrical engineering from the University of Bologna, Italy, in 1991, and the M.S. and Ph.D. degrees in electrical engineering from Stanford University in 1994 and 1997, respectively. He is an associate professor in the department of electronics and computer science in the University of Bologna. He also holds visiting researcher positions at Stanford University and the Hewlett-Packard Laboratories, Palo Alto, CA.Dr. Benini’s research interests are in all aspects of computer-aided design of digital circuits, with special emphasis on low-power applications, and in the design of portable systems. He is co-author of the book: Dynamic Power management, Design Techniques and CAD tools, Kluwer 1998.Dr. Benini is a member of the technical program committee for several technical conferences, including the Design Automation Conference, the International Symposium on Low Power Design and the International symposium on Hardware-Software Codesign.Davide Bertozzi received the B.S. degree in electrical engineering from the University of Bologna, Bologna, Italy, in 1999.He is currently pursuing the Ph.D. degree at the same University and is expected to graduate in 2003. His research interests concern the development of SoC co-simulation platforms, exploration of SoC communication architectures and low power system design.Alessandro Bogliolo received the Laurea degree in electrical engineering and the Ph.D. degree in electrical engineering and computer science from the University of Bologna, Bologna, Italy, in 1992 and 1998.In 1995 and 1996 he was a Visiting Scholar at the Computer Systems Laboratory (CSL), Stanford University, Stanford, CA.From 1999 to 2002 he was an Assistant Professor at the Department of Engineering (DI) of the University of Ferrara, Ferrara, Italy. Since 2002 he’s been with the Information Science and Technology Institute (STI) of the University of Urbino, Urbino, Italy, as Associate Professor. His research interests are mainly in the area of digital integrated circuits and systems, with emphasis on low power and signal integrity.Francesco Menichelli was born in Rome in 1976. He received the Electronic Engineering degree in 2001 at the University of Rome “La Sapienza”. From 2002 he is a Ph.D. student in Electronic Engineering at “La Sapienza” University of Rome.His scientific interests focus on low power digital design, and in particular in level tecniques for low power consumption, power modeling and simulation of digital systems.Mauro Olivieri received a Master degree in electronic engineering “cum laude” in 1991 and a Ph.D. degree in electronic and computer engineering in 1994 from the University of Genoa, Italy, where he also worked as an assistant professor. In 1998 he joined the University of Rome “La Sapienza”, where he is currently associate professor in electronics. His research interests are digital system-on-chips and microprocessor core design. Prof. Olivieri supervises several research projects supported by private and public fundings in the field of VLSI system design.     

Fluid coding and coexistence in ultra wide band networks

Time Hopping Ultra Wide Band (TH–UWB) commonly encodes the data symbols by shifting the position of the transmitted pulses by a quantity that is quantized over the inter-pulse interval range. In this paper, we relax the hypothesis of a discrete value for the time shift introduced by the TH code, by considering the possibility of generating real-valued codes that introduce time hopping in a “fluid” way. The effect on the power spectral density of generated signals is analyzed, and application of fluid coding to multiple access and to network coexistence is investigated by simulation. Portions of this work were presented at the 2005 2nd International Workshop Networking with Ultra Wide Band, Workshop on Ultra Wide Band for Sensor Networks [M.G. Di Benedetto, G. Giancola, D. Domenicali and P. Ingargiola “Fluid Coding in Time Hopping Ultra Wide Band Networks,” Proceedings of the IEEE 2nd International Workshop Networking with Ultra Wide Band—Ultra Wide Band for Sensor Networks, July 2005, Rome, Italy]. Daniele Domenicali took his Laurea degree in Telecommunications Engineering at the University of Rome La Sapienza in 2004. In November 2004 Domenicali wins the open competition for PhD scholarship in Information and Communication Engineering. He is teaching assistant for the course of “UWB Communication Systems” conducted by Professor Maria Gabriella Di Benedetto at the University of Rome La Sapienza. His research activity includes Pulse Shaping and the related modulation and coding techniques (Time Hopping Coding, PAM and PPM Modulation). Particular attention is paid to the effects produced in the Power Spectral Density, in order to find solutions capable of optimizing spectrum occupation while meeting the constraints imposed by emission masks. Daniele Domenicali is involved in the European Network of Excellence HYCON (Hybrid Control: Taming Heterogeneity and Complexity of Networked Embedded Systems). Guerino Giancola received the “Laurea” degree (magna cum laude) in Telecommunications Engineering, and the Ph.D. degree in Information and Communication Engineering from University of Rome La Sapienza, in 2001 and 2005, respectively. He is currently a research affiliate at the INFOCOM Department at University of Rome La Sapienza, where is actually holding the course of “Electrical Communications” for the degree on Electronic Engineering. His research interests include the analysis and modelling of Multi User Interference in Impulse Radio systems, and the design of Medium Access Control functions and protocols for UWB ad-hoc networks. Guerino Giancola recently co-authored with Prof. Maria-Gabriella Di Benedetto a book on Ultra Wide Band from radio to the network, titled “Understanding Ultra Wide Band Radio Fundamentals” and published by Prentice Hall in June 2004. He is now involved in the European project “PULSERS – Pervasive Ultra wideband Low Spectral Energy Radio Systems” and in the European Network of Excellence “HYCON- Hybrid Control: Taming Heterogeneity and Complexity of Networked Embedded Systems”. Guerino Giancola is a member of the IEEE Communication Society. Maria-Gabriella Di Benedetto obtained her Ph.D. in Telecommunications in 1987 from the University of Rome La Sapienza, Italy. In 1991, she joined the Faculty of Engineering of University of Rome La Sapienza, where currently she is a Full Professor of Telecommunications at the Infocom Department. She has held visiting positions at the Massachusetts Institute of Technology, the University of California, Berkeley, and the University of Paris XI, France. In 1994, she received the Mac Kay Professorship award from the University of California, Berkeley. Her research interests include wireless communication systems and speech science. From 1995 to 2000, she directed four European projects for the design of UMTS. Since 2000, she has been active in fostering the development of Ultra Wide Band (UWB) radio communications in Europe. Within the 5th framework, she directed for the Infocom Dept. two European projects (whyless.com and UCAN) aimed at the design and implementation of UWB ad-hoc networks. Currently, within the 6th EU Framework, her “Networking with UWB” research group participates in the PULSERS Integrated Project which will integrate UWB research and development in Europe for the next years, and in the LIAISON Integrated Project as regards the application of UWB to location-based services. She also participates in the HYCON network of excellence. Dr. Di Benedetto is co-edited several Special Issues on UWB communications and networks for several Journals including IEEE JSAC, Journal of Communications and Networks, Mobile Networks and Applications, Eurasip. In 2004, Dr. Di Benedetto co-authored with G. Giancola the first published book on UWB for communications titled “Understanding Ultra Wide Band Radio Fundamentals” and published by Prentice Hall. She recently completed the co-edition of two new books on UWB that will be published by 2005: UWB Communication Systems - A comprehensive overview, with T. Kaiser, D. Porcino, A. Molisch, and I. Oppermann, Hindawi Publishing Corporation, 2005, andUltra Wideband Wireless Communications with H. Arslan and Z.N. Chen, John Wiley & Sons, Inc., 2005.     

Packet concatenation at the IP level for performance enhancement in wireless local area networks

Wireless local area networks experience performance degradation in presence of small packets. The main reason for that is the large overhead added at the physical and link layers. This paper proposes a concatenation algorithm which groups IP layer packets prior to transmission, called PAC-IP. As a result, the overhead added at the physical and the link layers is shared among the grouped packets. Along with performance improvement, PAC-IP enables packet-based fairness in medium access as well as includes QoS support module handling delay-sensitive traffic demands. The performance of the proposed algorithm is evaluated through both simulations and an experimental WLAN testbed environment covering the single-hop and the widespread infrastructure network scenarios. Obtained results underline significant performance enhancement in different operating scenarios and channel conditions. Dzmitry Kliazovich received his Masters degree in Telecommunication science from Belarusian State University of Informatics and Radioelectronics in 2002. He is currently working towards the Ph.D. degree in University of Trento, Italy. From September 2005 to February 2006 he was a visiting researcher at the Computer Science Department of the University of California at Los Angeles. He is an author of more than 20 research papers published in international books, journals and conference proceedings. His main research interest lies in field of wireless networking with a focus on performance optimization and cross-layer design. Fabrizio Granelli was born in Genoa in 1972. He received the “Laurea” (M.Sc.) degree in Electronic Engineering from the University of Genoa, Italy, in 1997, with a thesis on video coding, awarded with the TELECOM Italy prize, and the Ph.D. in Telecommunications from the same university, in 2001. Since 2000 he is carrying on his teaching activity as Assistant Professor in Telecommunications at the Dept. of Information and Communication Technology—University of Trento (Italy). In August 2004, he was visiting professor at the State University of Campinas (Brasil). He is author or co-author of more than 60 papers published in international journals, books and conferences, and he is member of the Technical Committee of the International Conference on Communications (from 2003 to 2007) and Global Telecommunications Conference (GLOBECOM2003 and GLOBECOM2004). Dr. Granelli is guest-editor of ACM Journal on Mobile Networks and Applications, special issues on “WLAN Optimization at the MAC and Network Levels” and “Ultra-Wide Band for Sensor Networks”, and Co-Chair of 10th IEEE Workshop on Computer-Aided Modeling, Analysis, and Design of Communication Links and Networks (CAMAD’04). Dr. Granelli is General Vice-Chair of the First International Conference on Wireless Internet (WICON’05) and General Chair of the 11th IEEE Workshop on Computer-Aided Modeling, Analysis, and Design of Communication Links and Networks (CAMAD’06). His main research activities are in the field of networking and signal processing, with particular reference to network performance modeling, medium access control, wireless networks, cognitive radio systems, and video transmission over packet networks. He is Senior Member of IEEE and Associate Editor of IEEE Communications Letters.     

A Joint MAC-PHY Approach for Medium Access Control in VBR MC-CDMA Broadband Indoor Connections

Multicarrier Code Division Multiple Access (MC-CDMA) techniques were originally proposed at mid of 90's for wideband multi-user communications in wireless environments characterized by hostile propagation characteristics. In this work, the design of a MC-CDMA-based infrastructure is considered for VBR broadband indoor connections with real-time asynchronous multiple access. At the present time, Broadband Fixed Wireless Access (BFWA) standards like IEEE 802.16 and HIPERMAN can bring broadband services inside buildings, but indoor access should be conveniently provided by a local area connection. The capability of MC-CDMA of supporting asynchronous multi-user variable-bit-rate (VBR) transmission is exploited jointly with an efficient and real-time Medium Access Control (MAC) strategy in order to allow a significant number of indoor VBR users to transmit information in CDMA modality with different quality of service (QoS) profiles. Different classes of users are defined at the MAC level. The available radio resources (i.e. the orthogonal subchannels) are selectively attributed to transmitting users depending on their performance achieved at MAC level and measured by an “intelligent” gateway. When the quality level is not satisfactory for one or more users, the AP issues a decrease of the data rate for such users while providing them with an increased number of subcarriers, guaranteeing a slower transmission fostered against frequency-selective channel distortions. The paper presents an overview of the system and tests its performance through extensive simulations. The proposed joint MAC-PHY approach demonstrates good performance in terms of achieved throughput and high flexibility in radio resource management.This work has been partially supported in Italy by the “NETMOBS -Network-supported Mobility for the Student” – Create-NET project funding, 2005. Claudio Sacchi was born in Genoa (Italy) in 1965. He obtained the Laurea degree in Electronic Engineering, and the Ph.D. in Space Science and Engineering at the University of Genoa (Italy). Since August 2002, Dr. Sacchi has been holding a position as assistant professor at the Faculty of Engineering of the University of Trento (Italy). In 2004, he was appointed by the Department of Information and Communication Technology of the University of Trento as leader of the Research Program titled: “Wireless and Satellite Communications”. The research interests of Dr. Sacchi are focused on wideband mobile and satellite transmission systems based on space, time and frequency diversity, multi-user receivers based on non conventional techniques, and high-frequency ultra-wideband satellite communications. Dr. Sacchi is author and co-author of more than 40 papers published in international journals and conferences. He is member of IEEE. Giovanni Berlanda Scorza was born in Trento (Italy) in 1978. He received the Laurea in Telecommunications Engineering in 2002 at the “Politecnico di Milano” Technical University. Since October 2002, he is a Ph.D student at the Information and Communications Technologies (ICT) International Doctorate School of the University of Trento. His research interests mainly concern with specific aspects related to OFDM and MC-CDMA transmission techniques like e.g.: computationally-affordable multi-user receivers, Medium Access Control strategies, multicarrier-based multiplexing of multi-layered MPEG-4 coded video streams, etc. Fabrizio Granelli was born in Genoa in 1972. He received the “Laurea” (M.Sc.) degree in Electronic Engineering from the University of Genoa, Italy, in 1997, and the Ph.D. in Telecommunications from the same university, in 2001. Since 2000 he is carrying on his teaching activity as Assistant Professor in Telecommunications at the Dept. of Information and Communication Technology – University of Trento (Italy). In August 2004, he was visiting professor at the State University of Campinas (Brasil). He is author or co-author of more than 50 papers published in international journals, books and conferences, and he is member of the Technical Committee of the International Conference on Communications (ICC2003, ICC2004 and ICC2005) and Global Telecommunications Conference (GLOBECOM2003 and GLOBECOM2004). Dr. Granelli is guest-editor of ACM Journal on Mobile Networks and Applications, special issue on “WLAN Optimization at the MAC and Network Levels” and Co-Chair of 10th IEEE Workshop on Computer-Aided Modeling, Analysis, and Design of Communication Links and Networks (CAMAD'04). Dr. Granelli is General Vice-Chair of the First International Conference on Wireless Internet (WICON'05). His main research activities are in the field of networking and signal processing, with particular reference to network performance modeling, medium access control, wireless networks, next-generation IP, and video transmission over packet networks. Francesco G.B. De Natale received the Laurea in Electronic Engineering in 1990, and the Ph.D. in Telecommunications in 1994, both from the University of Genoa, Italy. In 1995–96 he was Visiting Professor at the University of Trento, Italy and from 1996 to 1999 Assistant Professor at the University of Cagliari, Italy. At present he is Full Professor of Telecommunications at the University of Trento, where he coordinates the didactic activities of the Bachelor and Master Courses in Telecommunications Engineering. Prof. De Natale is Deputy Head of the Dept. of Information and Communication Technologies, where he leads the research activities of the Multimedia Communications Lab. The research interests of Prof. De Natale are focused on image and signal processing, with particular attention to multimedia data compression, processing and transmission. He was General Co-Chair of the Packet Video Workshop in 2000 and is Technical Program Co-Chair of the IEEE Intl. Conf. on Image Processing to be held in 2005. In 1998 he was co-recipient of the IEEE Chester-Sall Best Paper Award. Prof. De Natale is a Senior Member of IEEE.     

A Comparative Evaluation of Designs for Reliable Memory Systems

This paper addresses the design of storage systems for operation under critical environmental conditions. For these applications, these systems should have low latency time in access, high performance in throughput and high storage capabilities; therefore, they must be assembled using highly reliable components, while allowing flexibility in design. Commercial Off The Shelf (COTS) components have often been used. A COTS-based architecture is analyzed in this paper; the proposed architecture uses design-level techniques (such as error detection/correction codes and scrubbing) to make commercially available Dynamic Random Access Memory (DRAM) chips tolerant to faults. This paper provides a complete and novel analysis of engineering alternatives which arise in the design of a highly reliable memory system based on Reed Solomon coding. A comparative analysis of methods for permanent fault detection is provided; moreover using a Markovian characterization, different functional arrangements (based on code and scrubbing frequency) are investigated and evaluated.Gian Carlo Cardarilli received the Laurea (summa cum laude) in 1981 from the University of Rome La Sapienza. He works for the University of Rome Tor Vergata since 1984. At present he is full professor of Digital Electronics and Electronics for Communication Systems at the University of Rome Tor Vergata. During the years 1992–1994 he worked for the University of L Aquila. During the years 1987/1988 he worked for the Circuits and Systems team at EPFL of Lausanne (Switzerland). Professor Cardarilli interests is in the area of VLSI architectures for Signal Processing and IC design. In this field he published over 140 papers in international journals and conferences. He also participated to the work group of JESSI-SMI for the support to the medium and small industries. For this structure he consulted different SMIs, designing a number ASICs, in order to introduce the microelectronics technology in the industry’s products. He has also regular cooperation with companies like Alenia Aerospazio, Rome, Italy, STM, Agrate Brianza, Italy, Micron, Avezzano, Italy, Ericsson Lab, Rome, Italy and with a lot of SMEs. Scientific interests of Professor Cardarilli concern the design of special architectures for signal processing. In particular, he works in the field of computer arithmetic and its application to the design of fast signal digital processor. He also developed mixed-signal neural network architectures implementing them in silicon technology. Recently, he also proposed different new solutions for the implementation of fault-tolerant architectures.Fabrizio Lombardi graduated in 1977 from the University of Essex (UK) with a B.Sc. (Hons.) in Electronic Engineering. In 1977 he joined the Microwave Research Unit at University College London, where he received the Master in Microwaves and Modern Optics (1978), the Diploma in Microwave Engineering (1978) and the Ph.D. from the University of London in 1982.He is currently the holder of the International Test Conference (ITC) Endowed Professorship at Northeastern University, Boston. At the same Institution during the period 1998–2004 he served as Chair of the Department of Electrical and Computer Engineering. Prior to Northeastern University he was a faculty member at Texas Tech University, the University of Colorado-Boulder and Texas A&M University.Dr. Lombardi has received many professional awards: the Visiting Fellowship at the British Columbia Advanced System Institute, University of Victoria, Canada (1988), twice the Texas Experimental Engineering Station Research Fellowship (1991–1992, 1997–1998) the Halliburton Professorship (1995), the Outstanding Engineering Research award at Northeastern University (2004) and an International Research award from the Ministry of Science and Education of Japan (1993–1999). Dr. Lombardi was the recipient of the 1985/86 Research Initiation award from the IEEE/Engineering Foundation and a Silver Quill award from Motorola-Austin (1996).Dr. Lombardi was an Associate Editor (1996–2000) of IEEE Transactions on Computers and a Distinguished Visitor of the IEEE-CS (1990–1993 and 2001–2004). Since 2000, he has been the Associate Editor-In-Chief of IEEE Transactions on Computers and an Associate Editor of the IEEE Design and Test Magazine. Since 2004 he serves as the Chair of the Committee on “Nanotechnology Devices and Systems” of the Test Technology Technical Council of the IEEE.Dr. Lombardi has been involved in organizing many international symposia, conferences and workshops sponsored by professional organizations as well as guest editor of Special Issues in archival journals and magazines such as the IEEE Transactions on Computers, IEEE Transactions on Instrumentation and Measurement, the IEEE Micro Magazine and the IEEE Design & Test Magazine. He is the Founding General Chair of the IEEE Symposium on Network Computing and Applications.His research interests are testing and design of digital systems, quantum and nano computing, ATE systems, configurable/network computing, defect tolerance and CAD VLSI. He has extensively published in these areas and edited six books.Marco Ottavi is currently postdoctoral research associate at the ECE Department of Northeastern University in Boston. He received the Laurea degree in Electronic Engineering from University of Rome “La Sapienza” in 1999 and the Ph.D. in Microelectronics and Telecommunications from University of Rome “Tor Vergata” in 2004. In 2000 he was with ULISSE Consortium, Rome as designer of digital systems for space applications. In 2003 he was visiting research assistant at ECE Department of Northeastern University. His research interests include yield and reliability modeling, fault-tolerant architectures, on-line testing and design of nano scale circuits and systems.Salvatore Pontarelli is currently postdoctoral research associate at the University of Rome, Tor Vergata. He received the Laurea degree in Electronic Engineering from the University of Bologna in 1999 and the Ph.D. in Microelectronics and Telecommunications Engineering from the University of Rome Tor Vergata in 2003. His research mainly focuses on fault tolerance, on-line testing and reconfigurable digital architectures.Adelio Salsano was born in Rome on December 26, 1941 and is currently full professor of Microelectronics at the University of Rome, Tor Vergata where he teaches the courses of Microelectronics and Electronic Programmable Systems. His present research work focuses on the techniques for the design of VLSI circuits, considering both the CAD problems and the architectures for ASIC design. In particular, of relevant interest are the research activities on fault tolerant/fail safe systems for critical environments as space, automotive etc.; on low power systems considering the circuit and architectural points of view; and on fuzzy and neural systems for pattern recognition. An international patent and more than 90 papers on international journals or presented in international meetings are the results of his research activity. At present he is the President of a national consortium named U.L.I.S.S.E., between ten universities, three polytechnics and several of the biggest national industries, as STMicroelectronics, ESAOTE, FINMECCANICA. He is responsible for contracts with the ASI, Italian Space Agency, for the evaluation and use in space environment of COTS circuits and for the definition of new suitable architectures for space applications. Professor Salsano is also involved in professional activities in the field of information technology and is also consultant of many public authorities for specific problems. In particular, he is consultant of the Departments of the Research and of the Industry, of IMI and of other authorities for the evaluation of industrial public and private research projects. Professor Salsano was a member of the consulting Committee for Engineering Sciences of the CNR (National Research Council) from 1981 to 1994 and participated in the design of public research programs in the fields of Telematics, Telemedicine, Office Automation, Telecommunication and, recently, Microelectronics and Bioelectronics.     

The ultra-wide bandwidth outdoor channel: From measurement campaign to statistical modelling

This paper proposes an investigation of the propagation behaviour for Ultra-Wide Bandwidth (UWB) signals in outdoor environments. Specifically, we first report on the results of an extensive measurement campaign carried out in three selected scenarios, namely “forest”, “hilly” and “sub-urban” environments. Then, we present the statistical model derived through the post-processing of collected samples by the CLEAN algorithm. While an extensive collection of results is provided in the paper, the main achievements can be summarized as follows: (i) the path-loss exponent varies from 2 to 3.5 and depends on the reference scenario and on the height of transmission and reception equipments with respect to the ground floor, (ii) the local mean of the received power experiences a Log-Normal shadowing with a standard deviation that may depend on the azimuth position, (iii) the statistics of the first received echo in the small-scale analysis also well fit a Log-Normal distribution; (iv) the delay spread in the small-scale multipath scenario turns out to be quite small (i.e. roughly 10 ns in the forest scenario and less than 32 ns in the sub-urban scenario). Marco Di Renzo (S’05) received the laurea degree (cum laude) in Electronic Engineering from the University of L’Aquila, Italy, in 2003. In 2002 he was with the Center of Excellence in Research DEWS (Design Methodologies for Embedded Controllers, Wireless Interconnections and System–on-Chip) at the Department of Electrical Engineering, University of L’Aquila, doing research on the analysis and design of Ultra Wide Band digital receiver architectures. Since 2003 he has been with the Department of Electrical Engineering, University of L’Aquila, where he worked on channel sounding and modelling for Ultra Wide Band systems and where he is currently pursuing his Ph.D. degree in Electric and Information Engineering. His current research activity is focused on channel modelling, synchronization and detection theory with specific interest to the Ultra Wide Band technology. In 2004 he played a key role in the successful creation of WEST Aquila S.r.l. (Wireless Embedded Systems Technologies Aquila), a R&D Spin-Off of the University of L’Aquila and the Center of Excellence in Research DEWS, where he currently holds the position of research engineer. Fabio Graziosi (S’96–M’97) was born in L’Aquila, Italy, in 1968. He received the Laurea degree (cum laude) and Ph.D. degree in electronic engineering from the University of L’Aquila, L’Aquila, Italy, in 1993 and 1997, respectively. Since February 1997 he has been with the Department of Electrical Engineering, at the University of L’Aquila, where he currently holds the position of Associate Professor. His current research interests are mainly focused on wireless communication systems with emphasis on wireless sensor networks and ultra wide band communication techniques. He is involved in major national and European research projects in the field of wireless systems. He is member of the Executive Committee of the Center of Excellence DEWS and serves as Chairman of the Board of Directors of WEST Aquila S.r.l., a Spin-off R&D Company of the University of L’Aquila and Center of Excellence DEWS, founded in December 2004. Riccardo Minutolo works in Thales Italia in the R&D department. He graduated in Electronic Engineering in the University of L’Aquila, in 1999. He joined Thomson-csf in 1999 working as junior engineer in the Radio propagation, interference and software development. In that period he gained expertise in HF, VHF, UHF, SHF radio propagation. In 2002 he joined Thales Italy (ex-Thomson-csf) working in the ad hoc networking area. In 2002 he was the National coordinator of a 3 years European international project (Euclide UWB). The Euclide UWB project aimed to study and research the potentiality of the emerging UWB technology for civil security and military purposes. Since 2002 his major areas of interest are: radio propagation, UWB physical layer, MAC and networking. Mauro Montanari was born in 1950 in Rimini and graduated in Electronic Engineering at Bologna University in 1974. He joined in 1976 Telettra, a national telecommunication company, working since the beginning in Defence R&D activities. His first experience was in the field of advanced automatic antenna matching unit in HF band. Afterwards he mastered, staying for several time periods in TRW—Redondo Beach/California, the technical issue of protecting radio communications through Spread Spectrum communications systems, in view of an important application to a new generation of tactical radio systems in VHF frequency band. On this topic he is co-author, with Prof. S. Pupolin of Padua University, of the book “Spread Spectrum Communications Systems” Collana Scientifica Telettra). From 1991 to 1998 he was responsible of the R&D Department within the Defence Division of Alcatel Italia (formerly Telettra) and in this position he managed several R&D projects: (i) Triservice Digital Network for the Italian MOD, in cooperation with Selenia Communications; (ii) SCRA (Single Channel Radio Access) and network management system for the Italian Army tactical network (SOTRIN) as a partner of Catrin Consortium; (iii) A new generation of radio equipment in HF band for fixed applications; (iv) High speed HF modem, according to several NATO waveforms; (v) HF fixed network for Italia Ministry of Foreign Affairs; (vi) Wide band Interception and jamming systems in HF band. Since 1999, he is responsible, within Thales Italia SpA—Land and Joint Systems Division, of Advanced Studies area with the task of promoting in the company new emerging technologies, specifically in the field of Wireless LAN, Tactical Internet, sensor networks, Ultra Wide Band for military applications and plasma antennas. This role includes establishing relations with most Thales R&D centres located in Europe and promoting new cooperative activities in new advanced technological areas. He also manages scientific relation with several Italian Universities. Fortunato Santucci (S’93–M’95–SM’00) was born at L’Aquila, Italy, in 1964. He received the laurea degree and the Ph.D. degree in Electronic Engineering from the University of L’Aquila, Italy, in 1989 and 1994, respectively. In 1989 he was with Selenia Spazio S.p.a., Rome, working on VSAT networks design. In 1991–1992 he was at the Solid State Electronics Institute (I.E.S.S.) of the National Research Council (C.N.R.), Rome, doing research on superconductor receivers for millimeter wave satellite systems. Since 1994 he has been with the Department of Electrical Engineering, University of L’Aquila, where he currently holds the position of Associate Professor. In 1996 he was a visiting researcher at the Department of Electrical and Computer Engineering of the University of Victoria, BC, Canada, where he researched on CDMA networks. His current research activity is focused on communication theory, access control and radio resource management in wireless systems, with special emphasis on technologies for networked embedded systems. He has participated in major national and European research programs in wireless mobile communications and coordinates research programs funded by industrial partners. He has been a reviewer for major technical journal in telecommunications and a session chairman in various conferences. He currently serves as an Editor for the IEEE Transactions on Communications and Kluwer Telecommunications Systems. He has been/is in the TPC of several conferences in communications. He is a Senior Member of the IEEE and is a member of the Communications Theory Committee. He is in the Executive Committee of the Center of Excellence DEWS at the University of L’Aquila and in the Executive Committee of CNIT.     

On Nash equilibria for multicast transmissions in ad-hoc wireless networks

We study a multicast game in ad-hoc wireless networks in which a source sends the same message or service to a set of receiving stations via multi-hop communications and the overall transmission cost is divided among the receivers according to given cost sharing methods. We assume that each receiver gets a certain utility from the transmission and enjoys a benefit equal to the difference between his utility and the shared cost he is asked to pay. Assuming a selfish and rational behavior, each user is willing to receive the transmission if and only if his shared cost does not exceed his utility. Moreover, given the strategies of the other users, he wants to select a strategy of minimum shared cost. A Nash equilibrium is a solution in which no user can increase his benefit by choosing to adopt a different strategy. We consider the following reasonable cost sharing methods: egalitarian, semi-egalitarian next-hop-proportional, path-proportional, egalitarian-path-proportional and Shapley value. We prove that, while the first five cost sharing methods in general do not admit a Nash equilibrium, the Shapley value yields games always converging to a Nash equilibrium. We then turn our attention to the special case in which the receivers’ set R is part of the input (that is only the stations belonging to R have a positive utility which is set equal to infinity) and show that in such a case also the egalitarian and the egalitarian-path-proportional methods yield convergent games. In such a framework, we show that the price of anarchy is unbounded for the game yielded by the egalitarian method and provide matching upper and lower bounds for the price of anarchy of the other two convergent games with respect to two different global cost functions, that is the overall cost of the power assignment, that coincides with the sum of all the shared costs, and the maximum shared cost paid by the receivers. Finally, in all cases we show that finding the best Nash equilibrium is computationally intractable, that is NP-hard. Vittorio Bilò received the degree in Computer Science and the Ph.D. degree in Computer Science at the University of L’Aquila in 2001 and 2005 respectively. He is currently an assistant professor at the Department of Mathematics “Ennio De Giorgi” of the University of Lecce. His research interests include algorithms and computational complexity, communication problems in interconnection networks and game theoretical issues in non-cooperative networks. Michele Flammini received the degree in Computer Science at the University of L’Aquila in 1990 and the Ph.D. degree in Computer Science at the University of Rome “La Sapienza” in 1995. He is full professor at the Computer Science Department of the University of L’Aquila since March 2005. His research interests include algorithms and computational complexity, game theory, communication problems in interconnection networks and routing. He has authored and co-authored more than 70 papers in his fields of interest published in the most reputed international conferences and journals. Giovanna Melideo received the Laurea degree in computer science in 1997 from the University of L’Aquila (Italy) and the Ph.D. degree in computer engineering in 2001 from the University of Rome “La Sapienza”. From November 1999 to February 2000 she was visitor at IRISA/INRIA, University of Rennes 1, Rennes (France) in the ADP group. She was research fellow from June to October 2001 at the University of L’Aquila, where she is currently an assistant professor in the Computer Science Department. Her research interests include algorithms and complexity, algorithmic game theory, wireless networks, models for information integration and cooperative information systems, certification and security in e-service, distributed protocols and dependability. She has been a member of the scientific and organizing committee of the IFIP international workshop on Certification and Security in E-Services (CSES 2002), Montreal, Canada. Luca Moscardelli received the degree in Computer Science at the University of L’Aquila in 2004. He is currently a Ph.D. student in Computer Science at the University of L’Aquila. His current research interests include optimization problems in social and communication networks, and the analysis of the interaction between selfish agents in non-cooperative networks.     

Pre-equalization Techniques for Downlink and Uplink TDD MC-CDMA Systems

Time division duplex (TDD) multi carrier-code division multiple access (MC-CDMA) systems have recently been proposed as potential candidates for next generation (4G) technology. In order to mitigate multiple access interference, in this paper we investigate pre-equalization schemes for both downlink and uplink transmissions, the former also in a multiple transmit antenna scenario. In particular, new pre-equalizer techniques are introduced and complexity issues addressed. Numerical results are given to highlight the effectiveness of the proposed schemes with respect to other existing pre-equalizer solutions. Paola Bisaglia was born in Padova, Italy, on August 8, 1971. She received the Laurea (cum laude) and Ph.D. degrees in electronic engineering from the University of Padova, Padova, Italy in 1996 and 2000 respectively. In 2000 she joined Hewlett-Packard Research Laboratories, Bristol, England, working on Home Phoneline Networking and wireless LANs. From 2002 she is a research fellow at the Department of Information Engineering of the University of Padova, Italy. Her research interests include wireless local area networks; modulation, coding techniques and detection strategies for next generation (4G) broadband cellular systems, based on the combination of multi-carrier and spread-spectrum modulations. Luca Sanguinetti is a Ph.D. Student of the University of Pisa. He was born in Empoli, Italy, on February 19, 1977, and he received the Doctor Engineer degree (cum laude) in information engineering from the University of Pisa, Italy, in 2002. Since 2002 he was with the Department of Information Engineering of the University of Pisa, where he is working toward the Ph.D. degree in information engineering under the supervision of Prof. Umberto Mengali and Prof. Michele Morelli. In 2004, he was a visiting Ph.D. student at the German Aerospace Center (DLR), Oberpfaffenhofen, Germany. Currently he is involved in a research project dealing with the design and the development of base stations and user terminals for wideband wireless communications systems able to cope with those reconfigurability and interoperability characteristics required by the next generation mobile communication systems. His research interests are in wireless communication theory, with emphasis on synchronization and detection algorithms and channel estimation in multiple-access communication systems. Michele Morelli received the Laurea (cum laude) in electrical engineering and the “Premio di Laurea SIP” from the University of Pisa, Italy, in 1991 and 1992 respectively. From 1992 to 1995 he was with the Department of Information Engineering of the University of Pisa, where he received the Ph.D. degree in electrical engineering. In September 1996 he joined the Centro Studi Metodi e Dispositivi per Radiotrasmissioni (CSMDR) of the Italian National Research Council (CNR) in Pisa where he held the position of Research Assistant. Since 2001 he has been with the Department of Information Engineering of the University of Pisa where he is currently an Associate Professor of Telecommunications. His research interests are in wireless communication theory, with emphasis on synchronization algorithms and channel estimation in multiple-access communication systems. Nevio Benvenuto received the Laurea degree from the University of Padova, Padova, Italy, and the Ph.D. degree from the University of Massachusetts, Amherst, in 1976 and 1983, respectively, both in electrical engineering. From 1983 to 1985 he was with AT&T Bell Laboratories, Holmdel, NJ, working on signal analysis problems. He spent the next three years alternating between the University of Padova, where he worked on communication systems research, and Bell Laboratories, as a Visiting Professor. From 1987 to 1990, he was a member of the faculty at the University of Ancona. He was a member of the faculty at the University of L'Aquila from 1994 to 1995. Currently, he is a Professor in the Electrical Engineering Department, University of Padova. His research interests include voice and data communications, digital radio, and signal processing. Silvano Pupolin received the Laurea degree in Electronic Engineering from the University of Padova, Italy, in 1970. Since then he joined the Department of Information Engineering, University of Padova, where currently is Full Professor of Electrical Communications. He was Chairman of the Faculty of Electronic Engineering from 1990 to 1994, Chairman of the PhD Course in Electronics and Telecommunications Engineering from 1991 to 1997 and Director of the PhD School in Information Engineering from 2004. Also, he was member of the programming and development committee from 1997 to 2002 and member of Scientific Committee from 1996 to 2001 of the University of Padova; member of the budget Committee of the Faculty of Engineering from 2003. He has been actively engaged in research on: Digital communication systems over copper wires and fiber optics; Spread spectrum communication systems; Design of large reliable communications networks; Effects of phase noise and HPA nonlinearities in OFDM systems; 3G mobile radio communications systems (UTRA-FDD and TDD) and beyond 3G (OFDM modulation and MC CDMA); Packet radio, Ad-hoc networks with the use of Bluetooth and WLAN. He was Chairman of the 9-th and 10-th Tyrrhenian International Workshop on Digital Communications devoted to “Broadband Wireless Communications” and to “Multimedia Communications”, respectively, and he was General Chair of the 7th International Symposium on Wireless Personal Multimedia Communications (WPMC'04). He spent the summer 1985 at AT&T Bell Laboratories on leave from Padova, doing research on digital radio systems. He was Principal investigator for research projects entitled “Variable bit rate mobile radio communication systems for multimedia applications”, “OFDM Systems with Applications to WLAN Networks”, and “MC-CDMA: an air interface for the 4th generation of wireless systems”.     

Security Framework for Wireless Sensor Networks

Wireless sensor network is more prone to adversary compare to common wireless network. This is due to the nature of wireless sensor network that involves many nodes, thus making the system more vulnerable. Another reason is the nature of wireless sensor network as an ad hoc network, making it having no hierarchal structure, complicating management tasks. Deploying new technology without security in mind has often proved to be unreasonably dangerous.One of the most fundamental rights in a 'healthy' society is the right of every citizen to be left alone. Article 12 of the U.N, Universal Declaration of Human Rights, states that “No one shall be subjected to arbitrary interference with his privacy, family, home or correspondence.”, in reality, though this right is increasingly being trod upon, along with undreamed of comforts and conveniences for the population in general. The digital revolution has made it possible to gather as well as store information about human behaviour on a massive scale. We leave electronic footprints everywhere we go, footprints that are being watched, analyzed and sold without our knowledge or even control.With this Security and Privacy solutions are mandatory aspects when developing new pervasive technologies such as wireless sensor networks (WSN).This paper analyses the security issues, threats and attacks and requirements of wireless sensor networks. This paper further proposes security framework and security architecture to integrate existing technologies with WSN technology, to provide secure and private communications to its users. Neeli Rashmi Prasad, Associate Professor and Head of Wireless Security and Sensor Networks Lab., part of Wireless Network including Embedded systems Group (WING), Center for TeleInfrastruktur (CTIF), Aalborg University, Aalborg, Denmark. She received her Ph.D. from University of Rome “Tor Vergata”, Rome, Italy, in the field of “adaptive security for wireless heterogeneous networks” in 2004 and M.Sc. (Ir.) degree in Electrical Engineering from Delft University of Technology, The Netherlands, in the field of “Indoor Wireless Communications using Slotted ISMA Protocols” in 1997. She joined Libertel (now Vodafone NL), Maastricht, The Netherlands as a Radio Engineer in 1997. From November 1998 till May 2001, she worked as Systems Architect for Wireless LANs in Wireless Communications and Networking Division of Lucent Technologies (now Agere Systems), Nieuwegein, The Netherlands. From June 2001 to July 2003, she was with T-Mobile Netherlands, The Hague, The Netherlands as Senior Architect for Core Network Group. Subsequently, from July 2003 to April 2004, she was Senior Research Manager at PCOM:I³, Aalborg, Denmark.During her industrial career she coordinated several projects. Just to name few major ones: country wide GSM landmass coverage (Vodafone NL), the impact of IP based security on Lucent WLAN (Wavelan later known as Orinoco) Access Points (APs), implementation of Virtual LAN and IAPP on Orinoco APs, VoIP implementation on APs, design and implementation of real-time embedded software platform for APs, mobile core network evolution towards All-IP for T-Mobile International to technical project lead for Public WLAN deployment for T-Mobile NL.Her publications range from top journals, international conferences and chapters in books. She has also co-edited and co-authored two books titled “WLAN Systems and Wireless IP for Next Generation Communications” and “Wireless LANs and Wireless IP Security, Mobility, QoS and Mobile Network Integration”, published by Artech House, 2001 and 2005. She has supervised several Masters Students projects.In December 1997 she won Best Paper award for her work on ISMA Protocol (Inhibit Sense Multiple Access). Her current research interest lies in wireless security, mobility, mesh networks, WSN, WPAN and heterogeneous networks.She was the Technical Program Committee Co-Chair IWS2005/WPMC05 held on September 18–22, 2005 in Aalborg. She is the Project Coordinator of EC Network of Excellence Project CRUISE on Wireless Sensor Networks. She is also cluster leader of EC Cluster for Sensor Networks. Mahbubul Alam, Ph.D. student at Center for TeleInfrastruktur (CTIF), Aalborg University, Denmark. He is with Cisco Systems, Inc. Netherlands from 2001 and worked as Consulting Systems Engineer in the field of mobile and wireless technology and since September 2002 he works as Business Analyst in areas of mobile, wireless and security. He is now based in Cisco Systems, Inc. San Jose, CA, USA, with focus on home networking, wireless and security. Previously he was with Siemens Netherlands as Systems Engineer and as Technical Team Leader of UMTS group. He received M. Sc. degree in Electrical & Electronic Engineering from Delft University of Technology, The Netherlands in 1998. He has published several papers at international conferences, journals, IEEE communication magazine and chapters for books. His research interest is in the field of wireless sensor networks.     

Analysis, testing and optimisation of electrostatic comb-drive levitational actuators

This work presents an analysis of the levitation effect in electrostatic comb fingers and of its possible use for vertical or torsional actuation of micromachined structures. Two different levitational mechanical resonators were designed and fabricated in a thick-polysilicon technology. A study of the dependence of the force intensity on the geometric parameters of the actuators were performed using FEM simulations, and information about critical geometrical parameters in the design of operative levitational actuators were obtained. The devices were characterized and the obtained results were compared with FEM simulations. Antonio Molfese received the M.S. degree cum laude in Electronic Engineering from the University of Pisa, Italy on March 2003. In the summer 2003 he was at IMEC, Belgium for an internship. On November 2003 he received the diploma degree cum laude in Industrial and Information Engineering from Scuola Superiore Sant'Anna di Studi Universitari e Perfezionamento of Pisa, Italy. He is currently pursuing the Ph.D. degree in Information Engineering at University of Pisa and he is working at IEIIT-Sezione di Pisa of Italian National Research Council (CNR) as research assistant. His main research interests include design, modeling and characterization of micro-electro-mechanical systems and microfluidics. Giovanni Pennelli was born on October 23, 1967 in Lucca, Italy. He graduated in 1992, cum laude, in Electronic Engineering. He obtained his Ph.D. in 1997 for a thesis entitled "New Materials for a Silicon-Based Optoelectronics". He moved to the University of Glasgow in April 1997 to work as a Research Assistant in the MBE group concerned with optoelectronic device fabrication and process development. He developed some MBE grown structures for HEMT applications. In September 2000, Dr Pennelli has been appointed assistant professor in the Department of Information Engineering, University of Pisa, Italy, pursuing research in electron beam lithography and nanometer scale process development. Francesco Pieri received the laurea and the Ph.D. degree in Electrical Engineering, both from the University of Pisa, Italy, in 1996 and 2000 respectively. He joined the Department of Information Engineering of the same University as an assistant professor in 2001. His current research interests include applications of porous silicon to sensors and microtechnologies, and development of microelectromechanical systems. Andrea Nannini received his laurea degree in Electronic Engineering from the University of Pisa, Italy, in 1982; He received his Ph.D. degree in 1987 at the end of the first Italian Ph.D. course held by the University of Padova, Italy. From 1988 to 1992 he was a Researcher at the “Scuola Superiore di Studi Universitari e Perfezionamento S. Anna” – Pisa- Italy. Since 1992 he joined the Department of Information Engineering of the University of Pisa as an Associate Professor. Since November 2000 he is a full professor of “Sensor and Microsystem Design”. He is currently chairman of the postgraduate school of Electronic Engineering and vice-chairman of the PhD school of Information Engineering of the University of Pisa. His main research interests concern solid state sensors, microelectronic devices and technologies, MEMS.     

Energy Efficiency of Error Control for High Data Rate WPAN

This paper addresses the issue of energy efficiency for error control mechanisms over WPAN systems. An analytical formulation has been developed to study the trade-off between link layer performance and energy consumption for two types of error control schemes: pure ARQ and type II hybrid ARQ protocol. An MC-CDMA-based system is considered. First of all, the analysis has been used to compare different error recovery schemes from the energy efficiency point of view. Moreover, it has been found that, for any channel conditions, there exists an optimal value of the transmit power that maximizes the energy efficiency. The paper also shows how this result can be used to design the power control of an energy efficient CDMA-based communication system. Mauro De Sanctis received the “Laurea' degree in Telecommunications Engineering from the University of Roma “Tor Vergata' in 2002. He is currently a Ph.D. Student and Assistant Professor in the Department of Electronics Engineering of the same University. He is involved in the DAVID (DAta and Video Interactive Distribution) satellite mission of the ASI (Italian Space Agency); his research is funded by the ASI. He is also involved in the MAGNET (My personal Adaptive Global NET) European FP6 integrated project and in the SatNEx European network of excellence. He worked on Italian national research projects on satellite-terrestrial systems integration such as SHINES (Satellite and HAP Integrated NEtworks and Services) and CABIS (CDMA for Broadband mobile terrestrial-satellite Integrated Systems). On autumn 2004 he joined the CTIF (Center for TeleInFrastructure), a research center focusing on modern telecommunications technologies located at the University of Aalborg (Denmark). His main areas of interest are: integration of different satellite networks, stratospheric platforms and terrestrial networks in a multi-layered fashion, internetworking and resource management in satellite systems and energy efficiency of WPAN systems. Simone Quaglieri received the “Laurea' degree cum laude in Telecommunications Engineering from the University of Roma “Tor Vergata', Italy, in 2004. His thesis, concerning the study of an analytic model for the Raman amplifier in optical systems with high bit rate, has been developed in the same University. During 2002 he worked as stagiaire on the design and development of optical submarine systems at the Elettra company (Telecom Italia group, Italy). He is joining the IRIS (Innovative Radio Integrated Systems) group at the University of Roma “Tor Vergata' as Research Engineer, where he is working on MC-CDMA based technology in the frame of the MAGNET (My Adaptive Global NETwork) European project. He is also working on error recovery mechanisms over satellite systems, and his research is funded by the EC in the frame of the SatNEx (Satellite Network of Excellence) European project. Ernestina Cianca graduated cum laude in Electronics Engineering in 1997 at the University of L'Aquila. She was with Italtel/Siemens (L'Aquila) from 1997 to 1998. She got her Ph.D. degree from the University of Rome Tor Vergata (URTV). The thesis work was on power management in CDMA-based satellite systems. She has been employed by the University of Aalborg, Denmark, in the Wireless Networking Groups (WING), as Research engineer (2000–2001) and as Assistant Professor (2001–2003). In particular, from Sept. 2002 she has been Technical Manager of Aalborg University for the IST-STRIKE project. She is currently Assistant Professor in Telecommunications at the URTV (Dpt. of Electronics Engineering), teaching DSP, Information and Coding. Her research mainly concerns wireless access technologies (CDMA and MIMO-OFDM-based systems), in particular, Radio Resource Management at PHY/MAC layer, ARQ/HARQ, TCP-IP issues over wireless links, integration of terrestrial and satellite systems. She has been the vice-coordinator of the following national research programs: CABIS, on CDMA integrated mobile systems (2000-2002) and SHINES, on satellite-HAP integrated networks for multimedia applications co-financed by MIUR (2002–2004). She is currently working on various European Projects: EU FP6 IP MAGNET (My personal Adaptive Global NET); EU ASIA LINK EAGER-NetWIC (Euro-Asian Network for Strengthening Graduate Education and Research in Wireless Communications); EU Network of excellence NEXWAY. She is author of about 40 papers, on international journals/transactions and proceedings of international conferences. Marina Ruggieri graduated in Electronics Engineering in 1984 at the University of Roma. She was: with FACE-ITT and GTC-ITT (Roanoke, VA) in the High Frequency Division (1985–1986); Research and Teaching Assistant at the University of Roma Tor Vergata (URTV) (1986–1991); Associate Professor in Telecommunications at the University of L'Aquila (1991–1994). Since November 2000 she is Full Professor in Telecommunications at the URTV (Dpt. of Electronics Engineering), teaching DSP, Information and Coding. In 1999 she has been appointed member of the Board of Governors of the IEEE AES Society (2000–2002) and re-elected for the period 2003–2005. Her research mainly concerns space communications and navigation systems (in particular satellites) as well as mobile and multimedia networks. She is the Principal Investigator of: satellite scientific communications missions (DAVID, WAVE) of ASI; national research programs (CABIS) on CDMA integrated mobile systems (2000–2002) and on satellite-HAP integrated networks for multimedia applications (SHINES), co-financed by MIUR (2002–2004). She co-ordinates the URTV Unit in various European Projects: EU FP6 IP MAGNET (My personal Adaptive Global NET); EU ASIA LINK EAGER-NetWIC (Euro-Asian Network for Strengthening Graduate Education and Research in Wireless Communications); EU Network of excellence NEXWAY; GALILEO JU 1st Call – July 2003: VERT (VEhicular Remote Tolling); and in the ASI program on V-band payloads (TRANSPONDERS). She is member of the Editorial Board of Wireless Personal Communications – an International Journal (Kluwer). She was awarded the 1990 Piero Fanti International Prize and she had a nomination for the Harry M. Mimmo Award in 1996 and the Cristoforo Colombo Award in 2002. She is author of about 170 papers, on international journals/transactions and proceedings of international conferences, book chapters and books.