无线OFDM系统信道软判决译码新方案  

A novel scheme for soft decision decoding in wireless coded OFDM communication systems

作　　者：王勇[1] 葛建华[1] 聂远飞[1] 

机构地区：[1]西安电子科技大学综合业务网理论及关键技术国家重点实验室,陕西西安710071

出　　处：《华中科技大学学报（自然科学版）》2007年第7期35-38,共4页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(60332030;60496316);国家高技术研究发展计划资助项目(2006AA01Z270)

摘　　要：提出了一种基于传输信道状态检测的无线正交频分复用(OFDM)系统自适应信道软判决译码方案.方案中,输入维特比译码器的数据可信度度量,可以根据当前信道信息和同频干扰检测结果自适应地变化,能有效解决传统信道软判决方法缺乏对当前信道进行自适应跟踪以及不适宜于高速移动接收的缺陷.仿真结果表明本方案在时变快衰落及存在同频干扰的无线信道下具有鲁棒性.Soft decision decoding techniques for wireless coded OFDM systems was investigated. A new method to estimate the channel state information for the Viterbi decoder is proposed, which overcomes the problem of reliability metric of transmitted signals in wireless as well as mobile channels. The CSI for each subcarrier is calculated as a properly defined squared Euclidean distance. On the basis of which, a soft decision decoding scheme to improve reception performance under multipath fading interference and cochannel interference from existing analog broadcasting signals is also proposed. The simulation results show that the scheme proposed can provide a compatible improvement to coded OFDM wireless communication system receiver.

关 键 词：正交频分复用 软判决译码 维特比译码 信噪比 信道状态信息 

分 类 号：TN919[电子电信—通信与信息系统]