다중사용자 OFDM 광대역 무선인터넷 시스템의 자원할당 방법

This study deals with the adaptive multiuser OFDM (Orthogonal Frequency Division Multiplexing) system which adjusts the resource allocation according to the environmental changes in such as wireless and quality of service required by users. The resource allocation includes subcarrier assignment to users, modulation method and power used for subcarriers. We first develop a general optimization model which maximizes data throughput while satisfying data rates required by users and total power constraints. Based on the property that this problem has the 0 duality gap, we apply the subgradient dual optimization method which obtains the solution of the dual problem by iteration of simple calculations. Extensive experiments with realistic data have shown that the subgradient dual method is applicable to the real world system, and can be used as a dynamic resource allocation mechanism.

[1]  Hui Liu,et al.  Dynamic resource allocation with finite buffer constraint in broadband OFDMA networks , 2003, 2003 IEEE Wireless Communications and Networking, 2003. WCNC 2003..

[2]  Yong-Hwan Lee,et al.  Transmit power and bit allocations for OFDM systems in a fading channel , 2003, GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489).

[3]  Didem Kivanc-Tureli,et al.  Computationally efficient bandwidth allocation and power control for OFDMA , 2003, IEEE Trans. Wirel. Commun..

[4]  Hui Liu,et al.  An efficient multiuser loading algorithm for OFDM-based broadband wireless systems , 2000, Globecom '00 - IEEE. Global Telecommunications Conference. Conference Record (Cat. No.00CH37137).

[5]  S. Pietrzyk,et al.  Multiuser subcarrier allocation for QoS provision in the OFDMA systems , 2002, Proceedings IEEE 56th Vehicular Technology Conference.

[6]  Pravin Varaiya,et al.  QoS aware adaptive resource allocation techniques for fair scheduling in OFDMA based broadband wireless access systems , 2003, IEEE Trans. Broadcast..

[7]  Youngnam Han,et al.  Optimal subchannel allocation scheme in multicell OFDMA systems , 2004, 2004 IEEE 59th Vehicular Technology Conference. VTC 2004-Spring (IEEE Cat. No.04CH37514).

[8]  Joachim Speidel,et al.  Efficient Subcarrier Allocation for Multiple Access in OFDM Systems , 2002 .

[9]  John M. Cioffi,et al.  Increase in capacity of multiuser OFDM system using dynamic subchannel allocation , 2000, VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026).