针对单载波频分多址(single carrier frequency division multiple access, SC-FDMA)系统的子信道相邻限制,研究了适用于SC-FDMA中继系统中最大化容量的资源分配算法,提出将该资源分配问题重构为一个集合划分问题,并借助运筹学中的相关算法求出最优解. 为降低最优资源分配算法的计算复杂度,还提出了一种采用贪婪试探法的次优算法. 仿真结果表明,在放大转发和解码转发中继协助的SC-FDMA系统中,最优算法的频谱利用率显著高于随机算法,而贪婪次优算法能达到接近最优算法的性能,并且具有较低的计算复杂度.
Resource allocation algorithms are proposed to maximize the capacity of single carrier frequency division multiple access (SC-FDMA) relay systems. Taking into account the subchannel adjacency restriction of SC-FDMA, an optimal algorithm is presented to reformulate this problem as a set partitioning problem.
By using the relevant methods in operations research, the optimal solution can be obtained. A suboptimal algorithm based on the greedy heuristic thinking is also proposed to reduce computational complexity of the optimal resource allocation. Simulation results show that, in amplify-and-forward and decode-and-forward relay-assisted SC-FDMA systems, spectral efficiency of the optimal algorithm is much higher than that of the random algorithm. The greedy algorithm with much lower complexity performs quite close to the optimal algorithm.
[1] MYUNG H G, LIM J, GOODMAN D J. Single carrier FDMA for uplink wireless transmission [J]. IEEE Vehicular Technology Magazine, 2006, 1(3): 30-38.
[2] 3GPP. Evolved Universal Terrestrial Radio Access (E-UTRA). Further advancements for E-UTRA physical layer aspects: TR 36.814 V9.0.0 [EB/OL]. http://www.3gpp.org/ftp/Specs/html-info/36814.htm, 2010-03-30.
[3] LOA K, WU C C, SHEU S T, YUAN Yi Fei, CHION M, HUO D, XU Ling. IMT-Advanced relay standards [J]. IEEE Communications Magazine, 2010, 48(8): 40-48.
[4] LANEMAN J N, TSE D N C, WORNELL G W. Cooperative diversity in wireless networks: efficient protocols and outage behavior [J]. IEEE Transactions on Information Theory, 2004, 50(12): 3062-3080.
[5] 万庆涛,马冠一. 放大-转发OFDMA中继系统多业务资源分配方案 [J]. 应用科学学报,2012, 30(1): 7-13.
WAN Qingtao, MA Guanyi. Resource allocation scheme for heterogeneous services in amplify-and-forward OFDM relay system [J]. Journal of Applied Sciences, 2012, 30(1): 7-13. (in Chinese)
[6] NAKADA M, TAKEDA K, ADACHI F. Channel capacity of SC-FDMA cooperative AF relay using spectrum division & adaptive subcarrier allocation [C]//IEEE International Conference on Network Infrastructure and Digital Content, Beijing, China, 2010: 579-583.
[7] BALAS E, PADBERG M. Set partitioning: a survey [J]. SIAM Review, 1976, 18(4): 710-760.
[8] ZHANG Jia Yi, YANG Lie Liang, HANZO L. Energy-efficient channel-dependent cooperative relaying for the multi-user SC-FDMA uplink [J]. IEEE Transactions on Vehicular Technology, 2011, 60(3): 992-1004.
[9] GOLDSMITH A. Wireless communications [M]. New York: Cambridge University Press, 2005: 214-216.
[10] WONG I C, OTERI O, MCCOY W. Optimal resource allocation in uplink SC-FDMA systems [J]. IEEE Transactions on Wireless Communications, 2009, 8(5): 2161-2165.
[11] RAPPAPORT T S. Wireless communications: principles and practice [M]. New Jersey: Prentice Hall, 2002.
[12] 3GPP. Technical Specification Group Radio Access network. Deployment aspects: TR 25.943 V11.0.0 [EB/OL]. http://www.3gpp.org/ftp/Specs/html-info /25943.htm, 2012-09-24.
[13] ZHANG Yingjun, LETAIEF K B. Multiuser adaptive subcarrier-and-bit allocation with adaptive cell selection for OFDM systems [J]. IEEE Transactions on Wireless Communications, 2004, 3(5): 1566- 1575.
[14] NG D W K, SCHOBER R. Cross-layer scheduling for OFDMA amplify-and-forward relay networks [J].IEEE Transactions on Vehicular Technology, 2010, 59(3): 1443-1458.