合作联盟中的节点选择及功率优化方法

Relay selection and power optimization in cooperative coalitions

无线网络中节点的合作通过形成联盟可以有效增大系统的安全容量。现有研究只是解决了联盟自身收益最大化的局部优化问题,没有从全局考虑联盟之间存在的竞争和干扰问题。文章首先基于联盟博弈理论,提出了实现物理层安全性能最大的分布式中继选择方案;在此基础上,针对联盟之间存在的干扰和竞争问题,基于有代价的非合作博弈,提出联盟功率的优化方法;根据优化后的联盟功率,联盟内的节点依据信道增益分配联盟的最优功率。仿真分析和性能比较表明,所提出的方法不仅可以形成稳定的联盟,与只考虑局部最优的安全性能相比较,降低了联盟的功率消耗,且提高了联盟的安全收益。

Through forming coalitions, the wireless node cooperation can improve the physical layer security capacity. The existing research only focuses on the partially optimal problem in the coalition without considering the competition and the interference among the coalitions. A distributed relay selection algorithm is proposed to achieve the maximum security performance based on the coalition game. The optimal power allocation algorithm is also proposed to deal with the competition and interference based on the non-cooperative game with the price. Then the optimal coalition power is divided by the node power according to the channel gain to the destination. The simulation results indicate that not only the stable coalition can be formed, the proposed algorithms effec- tively save the power cost and improve the security utilities of the coalition.