考虑中继时延的协作中继选择方法
Relay Selection Considering Relaying Delay in DF Cooperative Systems

针对数据业务可能在中继节点处排队等待发送，不能有效满足业务对时延要求的问题，在译码转发协作通信系统中建立了考虑中继时延的中继选择模型，提出了一种能有效降低数据业务在中继节点处的中继时延的中继选择方法，并进行了性能分析。首先推导了中继时延的概率密度函数，在此基础上通过进一步推导获得了基于所提方法的系统平均容量和中断概率。仿真结果与解析结果高度一致，并且表明：所提中继选择方法在保证传输速率前提下，可有效降低业务在中继节点处的平均时延，提高系统整体性能。
Aiming at the problem that the data traffic will be delayed at relays and the delay requirement of it may not be satisfied, a relay selection model with the consideration of the relaying delay is established in the two hop DF cooperative communication systems. On this basis, a new relay selection method considering the relaying delay of the service is proposed. The performances of the proposed method are also analyzed. First of all, the probability density function (PDF) of the relaying delay at the relays is derived. Thereafter, the analytical expressions of the average system capacity and outage probability are obtained. The simulation results are in accordance with the theory accurately and also verify that the proposed method can effectively reduce the average delay at relays while guaranteeing a considerable data rate.