分布式Alamouti空时码的信道容量及最优资源分配方案  

The Channel Capacity and Resource Allocation Scheme for Distributed Alamouti Space-Time Code

作　　者：种稚萌[1] 任品毅[1] 朱世华[1] 吕刚明[1] 

机构地区：[1]西安交通大学电子与信息工程学院,西安710049

出　　处：《电子与信息学报》2009年第1期27-31,共5页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(60372055);博士点基金(20030698027);国家高技术研究发展计划(2006AA01Z262)资助课题

摘　　要：该文针对基于译码转发协议的分布式Alamouti空时码(DF-DASTC)系统的信道容量以及最优资源分配策略问题。利用退化中继信道模型,推导得到了DF-DASTC系统在衰落信道下的信道容量闭式解。以DF-DASTC信道容量最大化为目标,对该系统在固定带宽分配时,中继及信源节点的最优功率分配方案进行了研究,推导得到了DF-DASTC系统的最优功率分配方案的闭式解。利用凸优化理论,将以DF-DASTC信道容量最大化为目标函数的多目标优化问题转换为非线性不等式约束的单目标凸优化问题,进一步得到了可变带宽分配时的DF-DASTC系统的最优带宽和功率分配策略。理论分析和系统仿真表明,该文所提出的资源分配策略,比平均分配的资源方案具有更大的信道容量。另外,该文的最优资源分配策略适用于具有多个中继节点的无线中继网络,具有普适性。In this paper, the channel capacity and the optimal resource allocation scheme for Distributed Alamouti Space-Time Code based on Decode-and-Forward （DF-DASTC） protocol are investigated. Using the degraded relay channel model, the channel capacity of DF-DASTC under fading channels is derived. To maximize the capacity of DF-DASTC, the closed-formed analytical expression of the optimal power allocation scheme with fixed bandwidth allocation is derived for DF-DASTC. Based on the convex optimization theory, the multi-objective optimization issue to maximize the capacity of DF-DASTC is converted into the general single objective optimization problem, and the optimal resource allocation scheme with variable bandwidth allocation is derived. Both theoretical analysis and simulations show that the resource allocation scheme can significantly increase the channel capacity of DF-DASTC. Moreover, the resource allocation scheme is a generalized method, which can be used in wireless relay networks with multiple relay nodes.

关 键 词：分布式空时码 信道容量 凸优化 资源分配 

分 类 号：TN929.5[电子电信—通信与信息系统]