tailieunhanh - Báo cáo hóa học: " Optimizing Transmission and Shutdown for Energy-Efficient Real-time Packet Scheduling in Clustered Ad Hoc 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: Optimizing Transmission and Shutdown for Energy-Efficient Real-time Packet Scheduling in Clustered Ad Hoc Networks | EURASIP Journal on Wireless Communications and Networking 2005 5 698-711 2005 Sofie Pollin et al. Optimizing Transmission and Shutdown for Energy-Efficient Real-time Packet Scheduling in Clustered Ad Hoc Networks Sofie Pollin 1 2 Bruno Bougard 1 2 Rahul Mangharam 1 3 Francky Catthoor 1 2 Ingrid Moerman 1 4 Ragunathan Rajkumar 3 and Liesbet Van der Perre1 1 Wireless Research IMEC 3001 Leuven Belgium Emails pollins@ bougardb@ catthoor@ vdperre@ 2 ESAT INSYS Katholieke Universiteit Leuven 3001 Leuven Belgium 3Real-Time Multimedia Systems Laboratory Carnegie Mellon University Pittsburgh PA 15213 USA Emails rahulm@ raj@ 4 INTEC Universiteit Gent 9000 Gent Belgium Email Received 30 June 2004 Revised 22 March 2005 Energy efficiency is imperative to enable the deployment of ad hoc networks. Conventional power management focuses independently on the physical or MAC layer and approaches differ depending on the abstraction level. At the physical layer the fundamental tradeoff between transmission rate and energy is exploited which leads to transmit as slow as possible. At MAC level power reduction techniques aim to transmit as fast as possible to maximize the radios power-off interval. The two approaches seem conflicting and it is not obvious which one is the most appropriate. We propose a transmission strategy that optimally mixes both techniques in a multiuser context. We present a cross-layer solution considering the transceiver power characteristics the varying system load and the dynamic channel constraints. Based on this we derive a low-complexity online scheduling algorithm. Results considering an M-ary quadrature amplitude modulation radio show that for a range of scenarios a large power reduction is achieved compared to the case where only scaling or shutdown is considered. Keywords and phrases clustered ad hoc networks energy efficiency lazy scheduling shutdown schedule-based MAC. 1. .