OFDM系统中多普勒分集技术研究与仿真  

Study and Simulation of Doppler Diversity in OFDM System

作　　者：李程[1] 王欣[1] 魏急波[1] 

机构地区：[1]国防科技大学电子科学与工程学院,长沙410073

出　　处：《信息化研究》2016年第2期17-22,共6页INFORMATIZATION RESEARCH

摘　　要：高速移动通信(如航空通信)中,由于收发节点的相对移动会产生较大的多普勒频移,从而使通信性能严重下降。多普勒分集技术将快时变信道中这种不利因素作为分集源,通过对信号做不同的分集处理再合并的方式来获得分集增益。文章重点研究正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统中多普勒分集技术,通过对接收时域信号作不同频移补偿信道多普勒效应,并使各支路信号相关性降低,然后对各支路信号作最大比合并、均衡。文章对正交频分复用系统多普勒分集信道估计、均衡以及支路参数选取做了描述,并仿真分析了均衡和不同支路频偏对分集性能的影响。In high-speed mobile communication, eg in aeronautical communication, the capacity will be decreased severely due to Doppler spread caused by motion of transceiver node. The Doppler diversity scheme takes advantage of this adverse factor occurred in fast time-varying channel and regard it as the source of diversity, obtaining diversity gain by different diversity schemes and combination schemes. Doppler diversity scheme in Orthogonal frequency division multiplexing （OFDM） which is mainly studied in this article compensate Doppler spread in channel by shifting the received time-domain signal on frequency domain, and thus decreased the relativity of signal on each branch, then combining and equalizing using MRC. This article has described the channel estimation, equalization and choosing of branch parameters, and simulated the diversity performance caused by equalization and different frequency shift.

关 键 词：正交频分复用 多普勒分集 频域均衡 

分 类 号：TN919.5[电子电信—通信与信息系统]