时分双工系统波束赋形块长优化  

Optimization on Beamforming Block Length in TDD Systems

作　　者：张雷[1,2] 周宝龙[1] 胡波[2] 李春亭[1] 

机构地区：[1]上海贝尔股份有限公司,上海201206 [2]复旦大学电子工程系,上海200433

出　　处：《电讯技术》2011年第1期1-6,共6页Telecommunication Engineering

基　　金：国家科技重大专项资助项目(2009ZX03002-001)~~

摘　　要：提出了一种优化时分双工系统波束赋形块长的方案。在该系统中,由于上下行链路的信道互易性,基站可以通过上行导频估计出当前时刻的信道状态信息,从而计算出下一时刻的发射波束赋形向量或矩阵。当给定归一化导频开销时,不同的波束赋形块长对应不同的上行信道估计误差和上下行传输时延,进而导致不同的系统性能。以块平均后验信噪比为目标函数,推导出最优块长,它能同时最大化块平均后验信噪比和块遍历容量(上界)。仿真结果验证了理论分析的正确性。A scheme is proposed to optinuze the beamfoming block length for time division duplex （TDD） systents in this paper. In this system, due to the channel reciprocity between uplink and downlink, the transmitter estimates the current channel state information （CSI） to generate the beamforIning vector/matrix for next trans- mission. Given normalized uplink pilot overhead, different beamforming block length causes different uplink channel estimation errors and uplink-downlink transmission delay, leading to different system performance. The optimal block length is derived aiming the average post SNR （Signal to Noise Ratio） per block. The obtained block length can maximize not only the average post SNR per block but also ergodie capacity （bound）. The simulation results confirm the validity of theoretical analysis.

关 键 词：波束赋形 块长优化 多入单出 时分双工 

分 类 号：TN929.5[电子电信—通信与信息系统]