tailieunhanh - Báo cáo hóa học: " Research Article Cross-Layer Dynamic Spectrum Map Management Framework for White Space Applications"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Cross-Layer Dynamic Spectrum Map Management Framework for White Space Applications | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2010 Article ID 870976 16 pages doi 2010 870976 Research Article Cross-Layer Dynamic Spectrum Map Management Framework for White Space Applications Seungil Yoon 1 Kyutae Lim 1 and Jongman Kim2 1 Georgia Electronic Design Center School of Electrical and Computer Engineering Georgia Institute of Technology Atlanta GA 30332 USA 2KORUS Research Center for Informersive Systems School of Electrical and Computer Engineering Georgia Institute of Technology Atlanta GA 30332 USA Correspondence should be addressed to Seungil Yoon syoon7@ Received 16 January 2010 Accepted 15 October 2010 Academic Editor Jordi Perez-Romero Copyright 2010 Seungil Yoon et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. White space unused TV spectrum will be allowed for unlicensed use by wireless communication devices the so called white space applications WSAs . WSAs retrieve a location-based spectrum map a list of open white space channels from a spectrum map server and can select one on the list as their operating channel for the broadband Internet access. However since not only primary users such as TV broadcasting services use white space shortly or longly but also neighboring WSAs do WSAs need to perform spectrum sensing that determines the occupancy status either occupied or unoccupied of white space channels and select one among the unoccupied channels according to the spectrum sensing results. In a conventional spectrum sensing they can execute unnecessary spectrum sensing on the already occupied channels. This paper proposes a dynamic management framework of white space that extends a spectrum map to contain occupancy information with the assistance of WSAs. Our framework enables WSAs to avoid unnecessary .