多频带混合场景下终端直通通信用户最优用户密度与功率分配研究  

Study on Optimal Density and Power Allocation for Device to Device Communication under Heterogeneous Networks with Multi-bands

作　　者：胡春静[1] 刘子扬[1] 彭博[1] 彭涛[1] 王文博[1] 

机构地区：[1]北京邮电大学泛网无线通信教育部重点实验室,北京100876

出　　处：《电子与信息学报》2014年第5期1171-1177,共7页Journal of Electronics & Information Technology

基　　金：国家科技重大专项(2012ZX03003011;2012ZX03003007);国家重点基础研究发展计划(2012CB316005);国家自然科学基金-广东联合基金(U1035001)资助课题

摘　　要：该文分析了蜂窝与终端直通(Device-to-Device,D2D)混合网络中多频带资源的场景下D2D用户最佳密度和功率分配问题。在混合网络中包含一个或者多个蜂窝网络,D2D用户复用蜂窝系统上行频谱资源。通过采用随机几何理论,上述问题可以建模成一个以最大化D2D网络容量为目标并以蜂窝用户和D2D用户的中断概率为约束条件的优化问题。由于上述优化问题非凸,因此分成两步解决原问题:首先证明当D2D用户密度确定的时候原问题对于功率分配是凸问题,并通过拉格朗日对偶方法得到了最优功率分配方案;随后证明中断约束条件将D2D用户密度的定义域分成有限个子区间,在每个子区间上可以通过求导的方式得到D2D传输容量局部最优解,基于上述两个结论,文中设计了一种子区间最优值搜索算法。通过仿真验证了算法的有效性,并且反映出D2D传输容量主要由中断约束条件和来自蜂窝网络的干扰决定。This paper analyzes the optimal density and power allocation for the D2D （Device-to-Device） communication in heterogeneous networks on multi-bands with target of maximizing the D2D transmission capacity. The heterogeneous networks contain one or several cellular systems, and the D2D communication shares uplink resources with them. By utilizing stochastic geometry, it is formed as a sum capacity optimization problem for the D2D network with constraints that guarantee outage probabilities of both cellular and the D2D transmissions. Since the original problem is non-convex, the proof work is divided into two steps：first, it is proved that the power allocation problem is convex when the D2D density is fixed, which can be solved by Lagrangian method;and then that the feasible region for the D2D user density is divided into finite sub-intervals by the outage constraints and the local maximum D2D transmission capacity can be obtained by the derivative method. A sub-interval linear searching algorithm based on the above conclusions is proposed. The simulation results demonstrate the effectiveness of the proposed algorithm and show that the optimal parameters of the D2D transmission is mainly affected by the outage constraints and the interference from cellular systems.

关 键 词：终端直通通信 网络容量 (M)PPP模型 多频带 

分 类 号：TN92[电子电信—通信与信息系统]