Đang chuẩn bị liên kết để tải về tài liệu:
Báo cáo hóa học: "Research Article Signal Classification in Fading Channels Using Cyclic Spectral Analysis"

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 Signal Classification in Fading Channels Using Cyclic Spectral Analysis | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2009 Article ID 879812 14 pages doi 10.1155 2009 879812 Research Article Signal Classification in Fading Channels Using Cyclic Spectral Analysis Eric Like 1 Vasu D. Chakravarthy 2 Paul Ratazzi 3 and Zhiqiang Wu4 1Air Force Institute of Technology Department of Electrical Engineering Wright-Patterson Air Force Base OH 45433 USA 2 Air Force Research Laboratory Sensors Directorate Wright-Patterson Air Force Base OH 45433 USA 3 Air Force Research Laboratory Information Directorate Griffiss Air Force Base NY 13441 USA 4 Department of Electrical Engineering Wright State University Dayton OH 45435 USA Correspondence should be addressed to Zhiqiang Wu zhiqiang.wu@wright.edu Received 4 May 2009 Accepted 13 July 2009 Recommended by Mischa Dohler Cognitive Radio CR a hierarchical Dynamic Spectrum Access DSA model has been considered as a strong candidate for future communication systems improving spectrum efficiency utilizing unused spectrum of opportunity. However to ensure the effectiveness of dynamic spectrum access accurate signal classification in fading channels at low signal to noise ratio is essential. In this paper a hierarchical cyclostationary-based classifier is proposed to reliably identify the signal type of a wide range of unknown signals. The proposed system assumes no a priori knowledge of critical signal statistics such as carrier frequency carrier phase or symbol rate. The system is designed with a multistage approach to minimize the number of samples required to make a classification decision while simultaneously ensuring the greatest reliability in the current and previous stages. The system performance is demonstrated in a variety of multipath fading channels where several multiantenna-based combining schemes are implemented to exploit spatial diversity. Copyright 2009 Eric Like et al. This is an open access article distributed under the Creative Commons .