针对基于中继的OFDM蜂窝网络,提出了一种基于合作中继的QoS感知子载波分配算法,即C-QSA(cooperative QoS-ware subcarrier allocation)算法。C-QSA算法利用基站与中继节点之间的合作传输机制来保证QoS业务的速率要求,允许中继节点进行比特重分配,充分利用无线系统的时变及多用户分集特性,提高无线资源的利用效率。C-QSA算法将子载波分配问题抽象为非线性整数规划,以最大化系统效用为目标,同时满足QoS业务的速率要求。仿真结果表明,C-QSA算法在用户效用及吞吐量等性能方面都有明显优势,系统实际效用接近理论最优值。
This paper proposed a QoS-aware subcarrier allocation algorithm for cooperative relay-based OFDM cellular network with both QoS and BE services,referred to as C-QSA. In C-QSA,employed cooperative transmission between the base-station (BS) and the relay-station (RS) to fulfill the requirements of QoS users. Moreover,allowed each RS to perform bit reallocation to fully exploit time-varying channel state and multiuser diversity,so as to achieve efficient radio resource utilization. C- QSA formulated the design of subcarrier allocation as a non-linear integer optimization problem,which aimed at maximizing the system sum utility while satisfying the data rate requirements of QoS users. Numerical results demonstrate that C-QSA is able to significantly improve the network performance in terms of user utility and system throughput,and the system utility achieved by C-QSA is very close to the optimal value.