Iterative receivers for SFBC-OFDM systems with adaptive training scheme  

SFBC-OFDM系统中基于自适应训练机制的迭代接收机(英文)

作　　者：井雅[1] 徐晓东[1] 陈明[1] 程时昕[1] 

机构地区：[1]东南大学移动通信国家重点实验室,南京210096

出　　处：《Journal of Southeast University(English Edition)》2005年第2期127-131,共5页东南大学学报（英文版）

基　　金：TheNationalHighTechnologyResearchandDevelopmentProgramofChina(863Program) (No. 2002AA123031)

摘　　要：This paper considers the design of iterative receivers for space-frequencyblock-coded orthogonal frequency division multiplexing (SFBC-OFDM) systems in unknown wirelessdispersive fading channels. An iterative joint channel estimation and symbol detection algorithm isderived. In the algorithm, the channel estimator performs alternately in two modes. During thetraining mode, the channel state information (CSI) is obtained by a discrete-Fourier-transform-basedchannel estimator and the noise variance and covariance matrix of the channel response is estimatedby the proposed method. In the data transmission mode, the CSI and transmitted data is obtainediteratively. In order to suppress the error propagation caused by a random error in identifyingsymbols, a simple error propagation detection criterion is proposed and an adaptive training schemeis applied to suppress the error propagation. Both theoretical analysis and simulation results showthat this algorithm gives better bit-error-rate performance and saves the overhead of OFDM systems.研究了在空频块码正交频分复用(SFBC OFDM)无线通信系统中适用于多径衰落信道下的迭代接收机的设计,导出了一种迭代的联合信道估计与符号检测的算法.在提出的算法中,信道估计器交替地工作于2种模式.在训练阶段,采用基于DFT的估计器估计出信道状态信息,并且采用所提出的算法估计出噪声方差和信道响应的互相关矩阵.在数据传输模式下,迭代地获得发送数据和信道状态信息.为了抑制由于符号检测中误判引起的错误传播,提出了一种简单的错误传播判定准则,并使用了一种自适应的训练机制来抑制误差传播.仿真结果显示,与传统的迭代算法相比,所提出的算法能够提供更好的误码性能,且节约了系统开销.

关 键 词：space-frequency block-coded orthogonal frequency division multiplexing(SFBC-OFDM) iterative receiver channel estimation adaptive training scheme 

分 类 号：TN911.5[电子电信—通信与信息系统]