多节点协同中继信道容量分析及功率分配

基于译码转发(DF)模式,在信道状态信息未知,源节点发射功率与各中继节点发射总功率分别受限于P1、P2的假设下,针对带直传(DT)和不带直传2种模型的多节点协同中继,进行了信道容量上下限的分析和推导。在功率限固定的情况下,分析了容量与中继节点数目之间的关系,给出了容量随中继节点数目增加而提高所需的条件。在功率限之和受限的情况下,获得了2个功率限的最佳分配。理论分析和仿真结果都表明:源到中继的信道条件较好时,只有当增加的新链路性能优于现有链路的平均值时才能提高容量;2种中继模型在功率限最佳分配下可获得最大容量。

Capacity analysis and power allocation of multi node cooperative relay channel

Based on DF mode,and under the power constraint P1 (source transmission) and P2 (total relay transmission),the capacity of multi node cooperative relay without CSI was analyzed，which is divided into two models: with DT and without DT. Given the fixed power constraint,the relationship between the capacity and the number of relay was achieved . The condition to improve the capacity as relay number increasing was proposed. When the sum of P1 and P2 was subject to another power constraint,the optimal power allocation was achieved. Theoretical analysis and simulation shows that when the channel condition between the source and the relay is better,the capacity increases only when the new link is better than the average existing links. The capacity is maximum at the optimal power allocation at two models.