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Báo cáo hóa học: " Advances in opportunistic radio technologies for TVWS"

Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí hóa hoc quốc tế đề tài : Advances in opportunistic radio technologies for TVWS | Noguet et al. EURASIP Journal on Wireless Communications and Networking 2011 2011 170 EURASIP Journal on . http jwcn.eurasipjournals.eom content 2011 1 170 Wireless Communications and Networking a SpringerOpen Journal RESEARCH Open Access Advances in opportunistic radio technologies for TVWS Dominique Noguet Matthieu Gautier and Vincent Berg Abstract Cognitive radio has been an active research area in wireless communications over the past 10 years. TV Digital Switch Over resulted in new regulatory regimes which offer the first large-scale opportunity for cognitive radio and networks. This article considers the most recent regulatory rules for TV White Space opportunistic usage and proposes technologies to operate in these bands. It addresses techniques to assess channel vacancy by the cognitive radio focusing on the two incumbent systems of the TV bands namely TV stations and wireless microphones. Spectrum-sensing performance is discussed under TV White Space regulation parameters. Then modulation schemes for the opportunistic radio are discussed showing the limitations of classical multi-carrier techniques and the advantages of filter bank modulations. In particular the low adjacent band leakage of filter bank is addressed and its benefit for spectrum pooling is stressed as a means to offer broadband access through channel aggregation. 1 Introduction Cognitive radio CR has been a major research topic in the radio communication community since it was introduced by Mitola in the early 2000s 1 . Cognitive Radio capitalizes on the flexible radio concept by setting the configuration of a flexible radio according to sensing and decision-making capabilities. Unfortunately large-scale deployment of CR in civil telecommunication systems was somewhat limited. This is mainly because its full benefits would require disruptive regulation rules where spectrum resources would be allocated according to actual needs at a specific location in space and time rather than ruled by .