双路径中继协议(two-path relaying,TPR)可以很大程度改善由于中继半双工产生的频谱效率损失,然而双路径中继协议的中继节点间干扰会严重影响系统传输速率,为此本文针对译码转发双路径中继协议,提出了一种启发性中继选择算法以最大化系统的传输速率性能.不同于现有的中继选择算法,该算法考虑了中继间干扰,其设计原则不仅基于当前时隙信道状态,还取决于被选中中继节点的上一时隙的信道状态.仿真结果证明启发式中继选择(heuristil relay selection,HRS)算法能够克服中继间干扰问题,以较低复杂度改善系统平均传输速率.
Spectral efficiency loss due to the half-duplex operated in relay nodes can be potentially improved by the two-path relaying(TPR)protocol.However,the mutual interference between the relay nodes can negatively affect the performance.Therefore,relay selection can be crucial to the system performance.In this paper,we propose a heuristic relay selection method for the decode-and-forward TPR strategy in order to maximize the transmission rate.Different from the existing relay selection methods,the inter-relay interference is considered.Meanwhile,the design principle of this method is based on not only the link conditions in current time slot,but also those of the relay node selected in previous time slot.Simulation results are conducted to verify the effectiveness of the proposed heuristic relay selection scheme.
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