TY - JOUR
T1 - Breaking spectrum gridlock with cognitive radios
T2 - An information theoretic perspective
AU - Goldsmith, Andrea
AU - Jafar, Syed Ali
AU - Maric, Ivana
AU - Srinivasa, Sudhir
N1 - Funding Information:
Dr. Goldsmith is a Fellow of Stanford. She has received several awards for her research, including the National Academy of Engineering Gilbreth Lectureship, the Alfred P. Sloan Fellowship, the Stanford Terman Fellowship, the National Science Foundation CAREER Development Award, and the Office of Naval Research Young Investigator Award. In addition, she was a corecipient of the 2005 IEEE Communications Society and Information Theory Society joint paper award. She currently is an Associate Editor for the IEEE TRANSACTIONS ON INFORMATION THEORY. She previously was an editor for the IEEE TRANSACTIONS ON COMMUNICATIONS and for the IEEE WIRELESS COMMUNICATIONS MAGAZINE, as well as a Guest Editor for several IEEE JOURNAL and MAGAZINE special issues. She participates actively in committees and conference organization for the IEEE Information Theory and Communications Societies and is an elected member of the Board of Governors for both societies. She is a Distinguished Lecturer for the IEEE Communications Society, is the First Vice President and President-Elect of the IEEE Information Theory Society, and was the Technical Program Cochair for the 2007 IEEE International Symposium on Information Theory. She also founded the Student Committee of the IEEE Information Theory Society. She is an inaugural recipient of Stanford’s postdoctoral mentoring award.
Funding Information:
Manuscript received September 29, 2008. First published April 24, 2009; current version published May 1, 2009. The work of A. Goldsmith and I. Marićwas supported in part by the DARPA ITMANET program under Grant 1105741-1-TFIND, Stanford’s Clean Slate Design for the Internet Program, and by the ARO under MURI award W911NF-05-1-0246. The work of S. A. Jafar and S. Srinivasa was supported by the National Science Foundation CAREER Award 0546860. A. Goldsmith and I. Marić are with the Wireless Systems Lab, Stanford University, Stanford, CA 94305 USA (e-mail: [email protected]; [email protected]). S. A. Jafar and S. Srinivasa are with the Electrical Engineering and Computer Science Department, University of California Irvine, Irvine, CA 92697-2625 USA (e-mail: [email protected]; [email protected]).
Funding Information:
Dr. Jafar received the NSF CAREER award in 2006 and the ONR Young Investigator Award in 2008. He received the UC Irvine Engineering Faculty of the Year award in 2006 and the UC Irvine EECS Professor of the Year award in 2009, for excellence in teaching. He is an Associate Editor for IEEE TRANSACTIONS ON COMMUNICATIONS and IEEE COMMUNICATIONS LETTERS.
PY - 2009/5
Y1 - 2009/5
N2 - Cognitive radios hold tremendous promise for increasing spectral efficiency in wireless systems. This paper surveys the fundamental capacity limits and associated transmission techniques for different wireless network design paradigms based on this promising technology. These paradigms are unified by the definition of a cognitive radio as an intelligent wireless communication device that exploits side information about its environment to improve spectrum utilization. This side information typically comprises knowledge about the activity, channels, codebooks, and/or messages of other nodes with which the cognitive node shares the spectrum. Based on the nature of the available side information as well as a priori rules about spectrum usage, cognitive radio systems seek to underlay, overlay, or interweave the cognitive radios' signals with the transmissions of noncognitive nodes. We provide a comprehensive summary of the known capacity characterizations in terms of upper and lower bounds for each of these three approaches. The increase in system degrees of freedom obtained through cognitive radios is also illuminated. This information- theoretic survey provides guidelines for the spectral efficiency gains possible through cognitive radios, as well as practical design ideas to mitigate the coexistence challenges in today's crowded spectrum.
AB - Cognitive radios hold tremendous promise for increasing spectral efficiency in wireless systems. This paper surveys the fundamental capacity limits and associated transmission techniques for different wireless network design paradigms based on this promising technology. These paradigms are unified by the definition of a cognitive radio as an intelligent wireless communication device that exploits side information about its environment to improve spectrum utilization. This side information typically comprises knowledge about the activity, channels, codebooks, and/or messages of other nodes with which the cognitive node shares the spectrum. Based on the nature of the available side information as well as a priori rules about spectrum usage, cognitive radio systems seek to underlay, overlay, or interweave the cognitive radios' signals with the transmissions of noncognitive nodes. We provide a comprehensive summary of the known capacity characterizations in terms of upper and lower bounds for each of these three approaches. The increase in system degrees of freedom obtained through cognitive radios is also illuminated. This information- theoretic survey provides guidelines for the spectral efficiency gains possible through cognitive radios, as well as practical design ideas to mitigate the coexistence challenges in today's crowded spectrum.
KW - Capacity
KW - Cognitive radio
KW - Degrees of freedom
KW - Interweave
KW - Overlay
KW - Side information
KW - Underlay
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U2 - 10.1109/JPROC.2009.2015717
DO - 10.1109/JPROC.2009.2015717
M3 - Article
AN - SCOPUS:67349259569
SN - 0018-9219
VL - 97
SP - 894
EP - 914
JO - Proceedings of the IEEE
JF - Proceedings of the IEEE
IS - 5
M1 - 4840529
ER -