OFDM系统中一种改进的线性内插方法.doc

文档介绍：
OFDM 系统中一种改进的线性内插方法
李星星,景晓军**
(北京邮电大学信息与通信工程学院,北京 100876)
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摘要:在 OFDM 系统中,信道估计的性能制约着接收机相干解调的可靠性。线性内插是基
于导频的信道估计中一个重要步骤,本文结合时间序列分析中的指数平滑提出了一种改进的
线性内插方法。对指数平滑方法进行了研究,从理论上分析了指数平滑抑制噪声的原理。假
设无线信道是慢衰落,通过仿真比较了改进方法与线性内插方法的性能,仿真结果表明改进
方法优于线性内插方法。
关键词:OFDM;信道估计;线性内插;指数平滑
中图分类号:
An Improved Linear Interpolation Method for OFDM
System
LI Xingxing, JING Xiaojun
(School of Information munication Engineering, Beijing University of Posts and
munications, Beijing 100876)
Abstract: In the OFDM system, the channel estimation is so significant that it affects the
reliability of coherent detection at the receiver side. Interpolation is an important step for pilot
aided channel estimation. In this paper, an improved linear interpolation bined with
exponential smoothing in time series analysis is proposed. A study of exponential smoothing has
helped to get a view of theoretical principles of how exponential smoothing suppresses the noise.
Under the assumption of slow fading wireless channel, the proposed method pared with
linear interpolation by simulation. The result of simulation indicates that the proposed method is
superior to linear interpolation.
Key words: OFDM; channel estimation; linear interpolation; exponential smoothing
0 引言
正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)是无线通信中一
种极具前景的技术,已经广泛应用于各种通信系统中。OFDM 系统中接收机相干