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GUEST EDITORIAL
DYNAMIC SPECTRUM MANAGEMENT IN WIRELESS NETWORKS ALIREZA BABAEI, JINWOO PARK, VÉRONIQUE V`EQUE, AND GAUTAM TRIVEDI
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ith the spectrum scarcity and underutilization of certain allocated bands, dynamic spectrum management (DSM) appears as an attractive solution. Novel techniques and technologies are needed to provide the necessary intelligence and adaptation for spectrum sharing and cooperation of multiple wireless networks. Under the so-called cognitive radio approach, environmentaware unlicensed wireless devices can share the spectrum with other licensed networks without degrading their performance and introducing unmanageable interference on the nodes of other networks. There are two ways for coexisting multiple networks to utilize the spectrum. First, the primary network, as the owner of the spectrum, makes a decision to share the spectrum with the secondary network based on a mutual agreement. Alternatively, the secondary network may access the spectrum opportunistically. The recent advances in a multiplicity of technologies involved, ranging from adaptive signal processing and spectral estimation techniques to power control and cooperative communications, have rendered this coexistence feasible. While some initial steps toward the implementation of DSM concepts have already been taken, there are still challenges that need to be tackled before their full potential can be achieved. This Special Issue aims to bring together certain recent work in the area of DSM and cognitive networks. The first article, “Dynamic Spectrum Access and Management,” is an invited article by Bijan Jabbari, Raymond Pickholtz, and Mark Norton. It provides an overview of the state of the art and envisioned techniques and technologies that may enable the next generation of spectrally efficient communications. The QoS maintenance and link management in a secondary network is a challenging and important issue due to dynamic behavior of channel availability for secondary users. In the second article, “Efficient QoS Support for Secondary Users in Cognitive Radio Systems,” Wilkomm and Wolisz propose redundancy of resources and reservation of resources as two approaches to ensure secondary users’ link maintenance. Neighbor discovery is an important step in a cognitive radio network before the configuration phase of the cognitive radio network (CRN). In the third article, “JENNA: A Jamming Evasive Network Coding Neighbor-Discovery Algorithm for Cognitive Radio Networks,” Asterjadhi and Zorzi propose a neighbor discovery algorithm and discuss its importance to resist against malicious and selfish cognitive users. The proposed algorithm is shown to be distributed, asynchronous, and robust to jamming attacks. The wideband spectrum sensing requirement and radio reconfiguration render the antenna design for cognitive radio systems a critically important issue for successful implementation of DSM systems. Nevertheless, this has not
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received enough attention in the research community. In the fourth article, “Spatial Spectrum Sensing for Wireless Handheld Terminals: Design Challenges and Novel Solutions Based on Tunable Parasitic Antennas,” Elpiniki et al. discuss the design challenges in spatial spectrum sensing (sensing in the angular and spectral dimensions) and propose a sensing approach based on parasitic antenna theory. Similar to the IEEE 802.22 wireless regional area network mainly intended for rural areas, TV white spaces can also be exploited to provide WiFi-like Internet access in urban areas. In the fifth article, “Understanding Wi-Fi 2.0: From the Economical Perspective of Wireless Service Providers,” Kim and Shin discuss optimal resource allocation with profit consideration and also market competition among wireless service providers. In the sixth article, “Docitive Networks: An Emerging Paradigm for Dynamic Spectrum Management,” Guipponi et al. introduce a new concept of docition, or teaching and dissemination of knowledge to facilitate the learning process in CRNs. The authors then consider docitive radios in the context of IEEE 802.22 for coexistence with digital TV broadcasting and show that docition improves the speed of convergence and the precision of the learning process. Due to spatial and temporal variation of users’ requirements for wireless services, the spectrum and infrastructure invested by wireless service providers may not always be used efficiently. Cooperation among service providers in terms of spectrum and infrastructure can help improve this efficiency. In the seventh article, “Cooperation among Wireless Service Providers: Opportunity, Challenges and Solution,” Lin et al. focus on spectrum-based cooperation and model spectrum cooperation using the group bargaining concept. In the eighth article, “Cognitive Femtocell Networks: An Overlay Architecture for Localized Dynamic Spectrum Access,” Gur et al. discuss a femtocell-based CR architecture that extends the femtocell concept for enabling cognitive operation. Experimental and simulation results are also provided to demonstrate potential benefits of the proposed architecture. As final words, we would like to take the opportunity to thank all the authors and reviewers for their contributions to this special issue. Our special thanks go to the Editor-in- Chief, Prof. Michael Fang, for his help and support during the editorial process. We hope you will find the collection of articles here of interest and of use.
BIOGRAPHIES ALIREZA BABAEI [M] (
[email protected]) received a Ph.D. degree in electrical and computer engineering from George Mason University (GMU), Virginia, in 2009. He is the recipient of an outstanding graduate student award from GMU and is currently a postdoctoral fellow at the Electrical and Computer Engineering Department of Auburn University. His areas of active research are wireless communications and networking, modeling and performance evaluation of random networks, and cognitive radio networks.
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GUEST EDITORIAL JINWOO PARK (
[email protected]) is a professor in the School of Electrical Engineering of Korea University. He received a B.S. degree in electronics engineering from Korea University and a Ph.D. degree in electrical engineering from Virginia Tech. He has served as a committee member for various international conferences and workshops in the area of communication networks, director of the Research Institute of Information and Communication Technologies of Korea University, director of the transport network division of the Optical Internet Forum, chairman of the BcN Development and Promotion Committee, and vice president of the Korea Information and Communications Society. He is now serving as a committee member of the Presidential Council of the Information Society and National Science of Technology Council of Korea, and a chair of Open Network Alliance. His research interests include the mobility management in all-IP networks and mobile IP network design. VÉRONIQUE VE` QUE [SM] (
[email protected]) received her engineering degree in computer science from Université Pierre et Marie Curie (Paris 6), France, in 1984 and a Master’s degree in computer science from the same university in 1985. Under the supervision of Professor Guy Pujolle, she obtained her Ph.D. degree in communication networks in 1989. From September 1989 to August 2000 she was an associate professor at Université de Paris Sud (Paris 11), France, and a research member with the Laboratory for Computer Science, Orsay, France. Since September 2000 she has worked as a full professor at the same university and a research member of the Institute of
IEEE Wireless Communications • August 2010
Electronics. Her research interests lie in the field of wireless, mobile, and high-speed communication networks with emphasis on resource allocation, QoS techniques, ad hoc routing, and performance evaluation. She has supervised 11 Ph.D. theses. She was co-author of a book on high-speed networks and ATM techniques in 1995. She has published more than 55 papers in international journals and conferences. Véronique Véque has been involved on the technical program committee of different IEEE conferences, including GLOBECOM, PIMRC, ISCC, WLN, and WiMOB, and regularly invited to chair some of their sessions. G AUTAM T RIVEDI (
[email protected]) currently heads the Mobile Systems Security Section at the U.S. Naval Research Laboratory (NRL). He has had extensive experience in various aspects of secure and resilient communications. From 1991 to 1996 he worked in the Information Systems Security program office at the Space and Naval Warfare Systems Command (SPAWAR), focusing on secure voice systems, both tactical and strategic. He worked in the Communications Security Systems section at the Naval Research Laboratory from 1996 until 2006, when he founded the Mobile Systems Security Section. His focus at NRL has been on wireless network security, and he has been involved in research projects in the areas of mobile ad hoc networking, discovery and localization of transmitters, software defined radios, antenna arrays, and cognitive radio networks. He holds B.S. and M.S. degrees in electrical engineering from the University of Illinois at Chicago and George Mason University, respectively.
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