华南理工大学学报(自然科学版) ›› 2013, Vol. 41 ›› Issue (5): 43-47,54.doi: 10.3969/j.issn.1000-565X.2013.05.007

• 电子、通信与自动控制 • 上一篇    下一篇

线性时变信道下OFDM 系统的加窗信道估计

解永生 汪明亮 周磊磊   

  1. 中国科学院上海微系统与信息技术研究所 无线传感器网络与通信重点实验室,上海 200050
  • 收稿日期:2012-09-01 修回日期:2012-09-10 出版日期:2013-05-25 发布日期:2013-04-01
  • 通信作者: 解永生(1984-) ,男,博士,主要从事无线传感器网络研究. E-mail:xieysh@gmail.com
  • 作者简介:解永生(1984-) ,男,博士,主要从事无线传感器网络研究.
  • 基金资助:

    国家科技重大专项( 2010ZX03006-003)

Windowed Channel Estimation of OFDM Systems in Linear Time-Varying Channels

Xie Yong-sheng Wang Ming-liang Zhou Lei-lei   

  1. Key Laboratory of Wireless Sensor Network & Communication,Shanghai Institute of Microsystem and Information Technology,Chinese Academy of Sciences,Shanghai 200050,China
  • Received:2012-09-01 Revised:2012-09-10 Online:2013-05-25 Published:2013-04-01
  • Contact: 解永生(1984-) ,男,博士,主要从事无线传感器网络研究. E-mail:xieysh@gmail.com
  • About author:解永生(1984-) ,男,博士,主要从事无线传感器网络研究.
  • Supported by:

    国家科技重大专项( 2010ZX03006-003)

摘要: 受时变性影响,正交频分复用( OFDM) 系统的频域信道矩阵是近似限带的.利用接收端窗函数可以增强信道的限带特性,但也导致信道无法采用线性模型进行表征.针对该问题,文中将窗函数与信道的时变性隔离开来,提出了加窗-线性信道模型.随后研究了该模型下的时变信道估计方法,并对该算法进行了简化,降低了算法的计算量.从仿真结果可以看出: 窗函数可以抑制信道矩阵的带外子载波间干扰; 与传统OFDM 系统的性能相比,文中算法的性能提升了约2.5 dB.

关键词: 正交频分复用, 信道估计, 子载波间干扰, 线性时变信道

Abstract:

Due to the time-varying characteristics,the channel matrix in the frequency domain of OFDM ( OrthogonalFrequency Division Multiplexing) system is approximately banded.Although the receiver window can improve theband-limited characteristics of time-varying channels,the equivalent channel cannot be modeled linearly.In orderto solve this problem,a new windowed-LTV ( Linear Time-Varying) model is proposed,which separates the timevaryingcharacteristics of the receiver window from those of the channel.Moreover,a time-varying channel estimationmethod of the model is investigated,and a simplified algorithm is presented to reduce the computational complexity.Simulated results show that the receiver window reduces the inter-subcarrier interference out of the band ofthe channel,and that,as compared with the traditional OFDM methods,the proposed algorithm brings about a performanceimprovement of 2.5 dB.

Key words: orthogonal frequency division multiplexing, channel estimation, inter-subcarrier interference, linear time-varying channel