Channel Estimation and Data Detection for OFDM Systems Over Fast-Fading and Dispersive Channels
Channel Estimation and Data Detection for OFDM Systems Over Fast-Fading and Dispersive Channels
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DOI：
10.1109/tvt.2009.2037639
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发表时间：
2010-03
影响因子：
6.8
通讯作者：
Wen Zhou;W. Lam
中科院分区：
文献类型：
--
作者：
Wen Zhou;W. Lam
快衰落信道的多普勒频移会产生载波间干扰，从而降低正交频分复用（OFDM）系统的性能。本文提出并研究了一种新的OFDM系统在快衰落色散信道下的信道估计和数据检测方法。提出了一种新的导频图案，它由梳状导频图案和分组导频图案组成。因此，与仅使用分组导频图案的情况相比，所需的导频子载波的数量显著减少。我们提出了建议的导频模式的基础上提出的信道估计的MSE分析和深入研究的MSE性能的信道估计的数值方法。已经导出了封闭形式的数学表达式，以将所提出的信道估计的MSE表示为多普勒频移、信道的可解析路径的数量、多项式阶数计算机仿真和数值结果都表明，基于所提出的导频模式的信道估计和数据检测可以有效地消除信道均方误差方面的ICI估计和误码率（BER）性能，而每个OFDM符号所需的导频数量与使用分组和均匀间隔的导频图案相比减少了约92.3%。
The Doppler shift of fast-fading channels will generate intercarrier interference (ICI) and, hence, degrade the performance of orthogonal frequency-division multiplexing (OFDM) systems. In this paper, a novel channel-estimation and data-detection method for OFDM systems over the fast-fading dispersive channels has been proposed and investigated. A new pilot pattern is also proposed, and it is composed of a comb-type pilot pattern and a grouped pilot pattern. The required number of pilot subcarriers is, therefore, significantly reduced compared with that of using the grouped pilot pattern only. We present the MSE analysis of the proposed channel estimation based on the proposed pilot pattern and thoroughly investigate the MSE performance of channel estimation by a numerical method. A closed-form mathematical expression has been derived to express the MSE of the proposed channel estimation as a function of the Doppler shift, the number of resolvable paths of the channel, the polynomial order, and so on. Both computer simulation and numerical results show that the proposed channel estimation and data detection based on the proposed pilot pattern have effectively eliminated the ICI in terms of the MSE of the channel estimation and bit-error-rate (BER) performance, whereas the required pilot number per OFDM symbol is reduced by about 92.3% in comparison with that of using the grouped and equispaced pilot pattern.