针对解码转发协作分集的分布式伙伴节点选择算法  

Distributed Partner Selection Algorithm for Decode-and-Forward Cooperative Diversity

作　　者：屈春河[1,2] 杨景[1,3] 张国清[1] 

机构地区：[1]中国科学院计算技术研究所,北京100190 [2]中国科学院研究生院,北京100049 [3]UT斯达康公司,北京100027

出　　处：《计算机学报》2010年第4期726-735,共10页Chinese Journal of Computers

基　　金：国家自然科学基金(60673168);国家“八六三”高技术研究发展计划项目基金(2006AA01Z207,2008AA01Z203)资助~~

摘　　要：该文研究了在解码转发协作分集系统中的伙伴节点选择问题.文中首先建立了伙伴节点选择问题的数学模型,其能够在伙伴节点和目的节点分别满足一定误比特率性能的前提下,使源节点和伙伴节点的发射功率之和最小化.因此,该模型不仅能够开发多用户无线系统所固有的空间分集能力,显著地提高无线传输性能,而且能够增加无线网络的通信容量和降低移动节点的能耗.文中还推导了在瑞利衰减信道中使用M-QAM(M-ary Quadra-ture Amplitude Modulation)时伙伴节点和目的节点的平均误比特率公式,从而揭示了系统性能与伙伴节点之间的依赖关系.根据数学模型和误比特率公式,文中提出了一种伙伴节点选择算法,能够在分布式的无线网络环境中以极小的控制协议开销,逐个消息地选择最优的伙伴节点参与转发消息.不仅如此,该算法还能够随着信道状态的变化动态地调整所选择的伙伴节点,所以对信道状态具有自适应能力.最后,文中通过仿真验证了所提出的算法.In this paper,the authors study the partner selection problem in decode-and-forward cooperative diversity systems.First,the authors present the mathematical model of the partner selection problem,which can minimize the total power consumption of the source and the partner subject to the average bit error rate （BER） constraints at the partner and the destination.Therefore,the model not only can exploit the inherent spatial diversity in multiuser wireless systems and remarkably enhance the transmission performance,but also can improve the capacity of wireless networks and conserve the power consumption in mobile nodes.In order to provide insight into the manner in which the performance depends on the partner,the authors then derive the closed-form average BER expressions at the partner and the destination for M-ary quadrature amplitude modulation （M-QAM） over Rayleigh fading channels.According to the mathematical model and these expressions,the authors propose a distributed partner selection algorithm,which can select the optimal partner to forward messages at the expense of little overhead in distributed wireless networks.In addition,the proposed distributed algorithm can dynamically adjust the selected partner in response to the changes of channel states.Accordingly,the algorithm can be adaptive to channel states.Furthermore,the authors present simulations to confirm the proposed algorithm.

关 键 词：协作分集 误比特率 伙伴节点选择 分布式算法 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]