移动中继协助下终端直通中面向能效的联合中继选择和资源分配方案

Energy-efficient Joint Relay Selection and Resource Allocation Scheme for Mobile Relay Aided Device-to-device Communication

在移动中继协助下的终端直通(Device-to-Device,D2D)中,由于频带复用,D2D链路与已有蜂窝链路会产生同频干扰。另外,考虑到终端设备功率受限,该文提出一种联合功率控制、信道分配和移动中继选择方案最大化D2D链路总能量效率。原问题为分数规划问题,可转化为通过Dinkelbach算法求解的参数规划问题,此外,上述参数规划问题可进一步分解为功率控制子问题和联合优化信道分配与移动中继选择子问题。其中,功率控制子问题属于DC(Difference-of-Concave)规划问题,其一般意义下为NP-hard难题,可借助序列凸优化方法得到有效的近似解,基于上述结果,联合优化信道分配与移动中继选择子问题可转化为二分图中的最大匹配问题,继而借助匈牙利算法在多项式时间内求得最优解。通过仿真,验证了该方案在优化能量效率的效果。

In mobile relay-aided Device-to-Device （D2D） communication, the co-channel interference between D2D links and the existing links is inevitable due to spectral reuse. Besides, considering the limited battery lifetime of mobile terminals, a joint Power Control （PC）, Channel Assignment （CA）, and MR-selection scheme is proposed to maximize the global energy efficiency of MR-aided D2D communication. By exploring the property of fraction programming, the original problem can be transferred into solving a sequence of parametric programming problems via the Dinkelbach method. Besides, each parametric programming problem can be decomposed into two subproblems, i.e., the PC subproblem and the joint CA and MR selection subproblem. Moreover, the former turns out to be the Difference-of-Concave （DC）, programming which is generally NP-hard, but it can be well addressed by sequential convex optimization technique. Based on the above results, the latter reduces to the bipartite matching problem which can be optimally solved by the Hungarian algorithm in polynomial time. Simulation results verify the efficacy of the proposed scheme.