基于统计信道状态信息的节能分布式中继选择

Energy-Efficient Distributed Relay Selection Based on Statistical Channel State Information

针对放大转发协作网络中的中继节点选择问题,提出了基于统计信道信息的能量有效分布式中继选择算法.算法对系统能量效率与系统中断性能进行折中,通过最小化系统平均消耗总功率来确定转发阈值,各中继节点根据转发阈值独立地决定是否参与数据转发.考虑有多个中继节点辅助源节点进行数据传输,提出了基于数值搜索方法确定转发阈值的多中继节点选择算法,在满足系统目标中断性能的同时,使系统消耗较少的平均功率.为了降低阈值求解的复杂度,考虑只有1个中继节点参与数据转发,进而提出了具有低计算复杂度的单中继节点选择算法.仿真结果表明,与已有的放大转发模式下的中继选择算法相比,该文提出的算法在能量效率上具有更好的系统性能.

In this paper, we propose a distributed relay selection algorithm based on statistical channel state information （CSI） in amplify-and-forward （AF） cooperative networks. A tradeoff is made between energy efficiency and system outage performance. A forwarding threshold is obtained by minimizing the average total power consumption. Each relay individually decides whether to participate in forwarding the source signals according to a forwarding threshold. A distributed multiple relay selection （DMRS） algorithm is proposed, in which all candidate relays have the possibility of forwarding the signals and the threshold is obtained by numerical search. The DMRS algorithm obtains good outage performance with low power consumption. A distributed single relay selection （DSRS） algorithm with low complexity is then investigated under the assumption that only one relay forwards the signals. Simulation results indicate that the proposed algorithms provide significant performance gain in terms of energy efficiency over the existing AF relay selection algorithms.