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Báo cáo hóa học: " Research Article Joint NC-ARQ and AMC for QoS-Guaranteed Mobile Multicast"

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 Joint NC-ARQ and AMC for QoS-Guaranteed Mobile Multicast | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2010 Article ID 807691 8 pages doi 10.1155 2010 807691 Research Article Joint NC-ARQ and AMC for QoS-Guaranteed Mobile Multicast Haibo Wang 1 Hans-Peter Schwefel 2 Xiaoli Chu 3 and Thomas Skj0deberg Toftegaard4 1 School of Electronics and Information Engineering Beijing Jiaotong University Beijing 100044 China 2 Department of Communication Technology Aalborg University and Telecommunications Research Center Vienna FTW 1220 Wien Austria 3 Department of Electronic Engineering King s College London London WC2R 2LS UK 4 Department of Computer Science Aarhus University 8000 Aarhus Denmark Correspondence should be addressed to Haibo Wang hbwang@bjtu.edu.cn Received 31 December 2009 Revised 14 May 2010 Accepted 30 June 2010 Academic Editor Wen Chen Copyright 2010 Haibo Wang 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. In mobile multicast transmissions the receiver with the worst instantaneous channel condition limits the transmission data rate under the desired Quality-of-Service QoS constraints. If Automatic Repeat reQuest ARQ schemes are applied the selection of Adaptive Modulation and Coding AMC mode will not necessarily be limited by the worst channel anymore and improved spectral efficiency may be obtained in the efficiency-reliability tradeoff. In this paper we first propose a Network-Coding-based ARQ NC-ARQ scheme in its optimal form and suboptimal form denoted as Opt-ARQ and SubOpt-ARQ resp. to solve the scalability problem of applying ARQ in multicast. Then we propose two joint NC-ARQ-AMC schemes namely the Average PERbased AMC AvgPER-AMC with Opt-ARQ and AvgPER-AMC with SubOpt-ARQ in a cross-layer design framework to maximize the average spectral efficiency per receiver under specific QoS .