针对瑞利双向中继信道,首先研究了满足总功率受限条件下使双向通信中断概率最小化的功率分配问题;然后推导出了最优功率分配的闭式解,指出最优功率分配方案总是将一半总功率分配给中继节点;最后研究了最佳中继节点位置选择问题,指出最佳中继节点位置位于2个用户之间连线的中点.结果表明,采用最优功率分配的双向中继传输相对于2个用户之间的直接传输,可以获得更低的中断概率.
In Rayleigh two-way relay channel,the power allocation problem aiming at minimizing the outage probability for bidirectional communication is investigated under the total power budget constraint.The closed-form solution for the optimal power allocation is developed.It shows that the optimal power allocation scheme always allocates half of the total power for the relay node.Furthermore,the best location for relay node is discussed.It indicates that the best relay location is at the right middle of the two end nodes.It is shown that two-way relay transmission with the optimal power allocation is superior to direct transmission in terms of outage probability.