基于信道统计特性的中继选择算法

A Statistic Channel Information-Based Relay Selection Scheme

该文提出了一种在非再生协作网络中,基于信道统计特性的最优中继选择方法。首先在等功率条件下,根据信道统计特性,定义一个等效信道增益的参数,该参数反映了中继节点在协作过程中两个阶段的信道特性。然后提出一种基于该参数的降序排列的中继选择方法。该方法在不同的信噪比范围内,选择不同的节点集合,使得系统的吞吐率中断概率最小。分析表明该选择方法的分集增益阶数能达到N+1,N为中继节点数目。仿真结果表明这种中继选择算法的中断概率性能优于其他算法。该方法进一步与功率分配相结合,构成了一种低复杂度的次优的中继选择方法。仿真结果表明这种次优算法能够取得和穷举算法相似的性能。

In this paper, a statistic channel information-based relay selection scheme is proposed in non-regenerative cooperative networks. Firstly, a parameter named equivalent channel gain is defined based on the statistic channel information under the equal power allocation constraint. It describes the compositive channel character of two phases in the cooperative process. Then an optimal relay selection scheme is proposed based on the descend order of equivalent channel gain. The scheme implies that different relay nodes should be selected to minimize the outage probability under different SNR ranges. And the analysis shows that the diversity order of the relay selection scheme is N ＋ 1, where N is the number of the relay node in the system. The numerical results show that the outage probability of the proposed scheme is lower than the other schemes. Moreover, a suboptimal relay selection scheme with power allocation is considered. The outage performance of the suboptimal scheme is nearly the same as the optimal exhaust search scheme while the complexity is reduced.