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Báo cáo hóa học: " Research Article Multiuser Radio Resource Allocation for Multiservice Transmission in OFDMA-Based Cooperative Relay Networks"

vTuyển 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 Multiuser Radio Resource Allocation for Multiservice Transmission in OFDMA-Based Cooperative Relay Networks | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2009 Article ID 940518 13 pages doi 10.1155 2009 940518 Research Article Multiuser Radio Resource Allocation for Multiservice Transmission in OFDMA-Based Cooperative Relay Networks Xing Zhang Shuping Chen and Wenbo Wang Wireless Signal Processing Networks Lab WSPN Key Lab of Universal Wireless Communications Beijing University of Posts and Telecommunications P.O. Box 93 Beijing 100876 China Correspondence should be addressed to Xing Zhang zhangx@bupt.edu.cn Received 29 July 2008 Accepted 20 October 2008 Recommended by Lingyang Song The problem of multiservice transmission in OFDMA-based cooperative relay networks is studied comprehensively. We propose a framework to adaptively allocate power subcarriers and data rate in OFDMA system to maximize spectral efficiency under the constraints of satisfying multiuser multiservices QoS requirements. Specifically first we concentrate on the single-user scenario which considers multiservice transmission in point-to-point cooperative relay network. Based on the analysis of single-user scenario we extend the multiservice transmission to multiuser point-to-multipoint scenario. Next based on the framework we propose several suboptimal radio resource allocation algorithms for multiservice transmissions in OFDMA-based cooperative relay networks to further reduce the computational complexity. Simulation results show that the proposed algorithms yield much higher spectral efficiency and much lower outage probability which are flexible and efficient for the OFDMA-based cooperative relay system. Copyright 2009 Xing Zhang 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. 1. Introduction Orthogonal frequency division multiple OFDM has received considerable research in recent .