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A dynamic resource allocation algorithm to satisfy the packet delay requirements for real-time services, while maximizing the system capacity in multiuser orthogonal frequency division multiplexing (OFDM) systems is introduced. Our proposed cross-layer algorithm, called Dynamic Subcarrier Allocation algorithm for Real-time Traffic (DSA-RT), consists of two interactive components. In the medium access control (MAC) layer, the users' expected transmission rates in terms of the number of subcarriers per symbol and their corresponding transmission priorities are evaluated. With the above MAC-layer information and the detected subcarriers' channel gains, in the physical (PHY) layer, a modified Kuhn-Munkres algorithm is developed to minimize the system power for a certain subcarrier allocation, then a PHY-layer resource allocation scheme is proposed to optimally allocate the subcarriers under the system signal-to-noise ratio (SNR) and power constraints. In a system where the number of mobile users changes dynamically, our developed MAC-layer access control and removal schemes can guarantee the quality of service (QoS) of the existing users in the system and fully utilize the bandwidth resource. The numerical results show that DSA-RT significantly improves the system performance in terms of the bandwidth efficiency and delay performance for real-time services.
Lawrey E: Multiuser OFDM. Proceedings of the International Symposium on Signal Processing and Its Applications (ISSPA '99), August 1999, Brisbane, Australia 761-764.
Bhagwat P, Krishna A, Tripathi S: Enhancing throughput over wireless LAN's using channel state dependent packet scheduling. Proceedings of 17th Annual Joint Conference of the IEEE Computer and Communications Societie (INFOCOM '98), March 1998, San Francisco, Calif, USA 1103-1111.
Andrews M, Kumaran K, Ramanan K, Stolyar A, Whiting P, Vijayakumar R: Providing quality of service over a shared wireless link. IEEE Communications Magazine 2001, 39(2):150-153. 10.1109/35.900644 CrossRef
Zhang YJ, Liew SC: Link-adaptive largest-weighted-throughput packet scheduling for real-time traffics in wireless OFDM networks. Proceedings of IEEE Global Telecommunications Conference (GLOBECOM '05), November-December 2005, St. Louis, Mo, USA 5: 2490-2494.
Cheong YYW, Tsui CY, Cheng RS, Letaief KB: A realtime sub-carrier allocation scheme for multiple access downlink OFDM transmission. Proceedings of the 49th IEEE Vehicular Technology Conference (VTC '99), September 1999, Amsterdam, The Netherlands 2: 1124-1128.
Diao Z, Shen D, Li VOK: CPLD-PGPS scheduler in wireless OFDM systems. IEEE Transactions on Wireless Communications 2006, 5(10):2923-2931. CrossRef
Zhu J, Bing B, Li Y, Xu J: An adaptive subchannel allocation algorithm for OFDM-based wireless home networks. Proceedings of the 1st IEEE Consumer Communications and Networking Conference, (CCNC '04), January 2004, Las Vegas, Nev, USA 352-356.
Bertsekas D, Gallager R: Data Networks. 2nd edition. Prentice-Hall, Englewood Cliffs, NJ, USA; 1992. MATH
West DB: Introduction to Graph Theory. Prentice-Hall, Englewood Cliffs, NJ, USA; 2001.
Kwon E, Kim S-G, Lee J: Overload control with removal algorithm for real-time flows in wireless networks. Proceedings of the IEEE 63rd Vehicular Technology Conference (VTC '06), May 2006, Melbourne, Australia 3: 1127-1131.
Cai J, Shen X, Mark JW: Downlink resource management for packet transmission in OFDM wireless communication systems. Proceedings of IEEE Global Telecommunications Conference (GLOBECOM '03), December 2003, San Francisco, Calif, USA 6: 2999-3003.
Xiao C, Zheng YR, Beaulieu NC: Second-order statistical properties of the WSS Jakes' fading channel simulator. IEEE Transactions on Communications 2002, 50(6):888-891. 10.1109/TCOMM.2002.1010606 CrossRef
- Dynamic Subcarrier Allocation for Real-Time Traffic over Multiuser OFDM Systems
Victor O. K. Li
- Springer International Publishing
- EURASIP Journal on Wireless Communications and Networking
Elektronische ISSN: 1687-1499
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