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báo cáo hóa học: " Optimal modulation and coding scheme allocation of scalable video multicast over IEEE 802.16e networks"

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: Optimal modulation and coding scheme allocation of scalable video multicast over IEEE 802.16e networks | Tsai et al. EURASIP Journal on Wireless Communications and Networking 2011 2011 33 http jwcn.eurasipjournals.eom content 2011 1 33 o EURASIP Journal on Wireless Communications and Networking a SpringerOpen Journal RESEARCH Open Access Optimal modulation and coding scheme allocation of scalable video multicast over IEEE 802.16e networks Chia-Tai Tsai Rong-Hong Jan and Chien Chen Abstract With the rapid development of wireless communication technology and the rapid increase in demand for network bandwidth IEEE 802.16e is an emerging network technique that has been deployed in many metropolises. In addition to the features of high data rate and large coverage it also enables scalable video multicasting which is a potentially promising application over an IEEE 802.16e network. How to optimally assign the modulation and coding scheme MCS of the scalable video stream for the mobile subscriber stations to improve spectral efficiency and maximize utility is a crucial task. We formulate this MCS assignment problem as an optimization problem called the total utility maximization problem TUMP . This article transforms the TUMP into a precedence constraint knapsack problem which is a NP-complete problem. Then a branch and bound method which is based on two dominance rules and a lower bound is presented to solve the TUMP. The simulation results show that the proposed branch and bound method can find the optimal solution efficiently. Keywords Adaptive modulation and coding Branch and bound algorithm IEEE 802.16e Resource allocation Scalable video coding 1 Introduction With the popularity of wireless networks the need for network bandwidth is growing rapidly. In order to provide high quality service various categories of broadband wireless network techniques e.g. IEEE 802.16e or WiMAX Worldwide Interoperability for Microwave Access and 3GPP LTE have been proposed. Among these techniques IEEE 802.16e is an emerging network technique and has been deployed in many metropolises e.g.