均值反馈下信息与能量传输系统的预编码设计  

The Precoder Design in Wireless Information and Energy Transmission Systems with Mean Feedback

作　　者：周雯[1] 吴寅 ZHOU Wen;WU Yin(College of Information Science and Technology,Nanjing Forestry University,Nanjing,Jiangsu 210018,China)

机构地区：[1]南京林业大学信息科学技术学院,江苏南京210018

出　　处：《信号处理》2018年第10期1151-1159,共9页Journal of Signal Processing

基　　金：国家自然科学基金(61601275;31700478);南京林业大学高学历人才基金(GXL2016030);广东省自然科学基金(2016A030313068)

摘　　要：该文研究了多天线信息与能量联合传输系统的最优预编码设计问题,其中发送端只具备信道均值反馈信息。预编码设计目标是最大化系统信息传输速率的期望值,同时满足能量接收机的最低能量要求。将该问题归结为一个半正定规划,进一步转换成对偶问题并且证明了两个问题是等价的;然后采用协方差矩阵分解技术,把对偶问题的约束消除,变为无约束的优化问题,提出了基于梯度下降的搜索算法进行求解。此外,该文还给出了关于信息-能量可达域边界的引理,提供了两个关键边界点。仿真实验验证了提出预编码算法的收敛性,给出了若干系统配置下的系统信息-能量可达域。结果表明,与若干经典发送方案相比,提出算法的信息-能量可达域更加广阔。In this paper,the optimal precoder is designed for simultaneous wireless information and power transfer in multiple-input multiple-output(MIMO)systems with the mean channel state information.The objective of the precoder design is to maximize the expected system information rate,meanwhile meeting the minimum energy requirement of the energy receiver.We formulate the problem as a semi-definite programming(SDP),further transform it into a dual problem,and prove the two problems are equivalent.Based on the technique of covariance matrix decomposition,we transform the constrained optimization problem into an unconstrained one and propose a gradient-decent searching method to solve this problem.Besides,we also provide a lemma on the boundary of the achievable rate-energy(R-E)region,in which two important boundary points are provided.Computer simulation has been deployed to demonstrate the convergence of the proposed precoding algorithm and present achievable R-E regions under a few system settings.The results show that,the proposed method has much broader R-E regions,in comparison with a few classical transmission schemes.

关 键 词：多入多出 预编码 信息与能量传输 均值反馈 

分 类 号：TN929.5[电子电信—通信与信息系统]