摘要
本文对中继辅助的多输入多输出(MIMO)系统中信源与中继的联合最优功率分配问题进行了研究.首先,基于系统容量最大化准则提出相应代价函数,并证明了该代价函数仅仅对于部分参数是凸的,而对于全局参数是非凸的.然后,通过推导系统容量的下界,给出了一个新的代价函数,从而将非凸问题转化为一个联合凸优化问题.最后,利用凸优化方法获得了联合功率分配问题的全局最优解.计算机仿真表明,与现有方案相比,所提方案获得了更好的吞吐量性能.
The joint optimal power allocation（PA） problem is investigated for the MIMO system enhanced by relay in this paper.Firstly,based on the maximization of the capacity,a cost function is formulated for the joint PA optimization,where the cost function thus obtained is proved to be only convex with respect to the partial parameters but not convex with respect to the whole parameter.Secondly,a modified cost function is obtained by derived a tight lower bound of the capacity,and thus the original nonconvex problem is converted into a convex problem.Finally,a global optimum is obtained by using the convex optimization methods for the joint power allocation problem.It is confirmed through computer simulations that the proposed PA scheme outperforms the existing method in terms of the capacity.
出处
《电子学报》
EI
CAS
CSCD
北大核心
2010年第10期2214-2218,共5页
Acta Electronica Sinica
基金
国家973重点基础研究发展规划(No.2007CB310603)
国家自然科学基金(No.61071113
No.60672093
No.60702029)
国家863高技术研究发展计划(No.2007AA01Z262)
国家科技重大专项(No.2009ZX03003-004)
关键词
多输入多输出
中继
功率分配
凸优化
multiple-input multiple-output（MIMO）
relay
power allocation
convex optimization
