通过基站的反馈信息,一个固定中继节点可以用一个OFDM符号同时帮助多个源用户转发信息,这样可以有效地利用带宽。因此,为了进一步提高系统容量,降低中断概率,先在中继节点间进行子载波调整,然后以获取信道容量最大为原则,提出了源用户和中继节点间子载波配对和功率分配的联合优化算法。仿真结果表明,相对于随机中继子载波选择算法以及平均功率分配算法,所提算法的中继系统容量有较大提升,同时中断概率有较为明显的下降。
By exploiting limited feedback from the base station,one fixed relay is able to help forward information of multiple sources in one OFDM symbol which can efficiently utilize the available bandwidth.To further improve the system capacity and reduce the outage probability,firstly the sub-carriers among the relays was adjusted.Then joint sub-carrier matching and power allocation scheme to maximize the channel capacity was proposed.Comparing with random sub-carrier matching algorithm and equal power allocation algorithm,the simulation results show that the scheme will greatly improve the system capacity and reduce the outage probability.