Channel estimation techniques based on pilot arrangement in OFDM systems
Channel estimation techniques based on pilot arrangement in OFDM systems
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DOI：
10.1109/tbc.2002.804034
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发表时间：
2002-09-01
影响因子：
4.5
通讯作者：
Bahai, A
中科院分区：
文献类型：
--
作者：
Coleri, S;Ergen, M;Bahai, A
研究了基于导频排列的正交频分复用系统的信道估计技术。通过不同的导频信道估计算法和信道内插算法，研究了基于梳状导频排列的信道估计。导频信道的估计基于LS和LMS，而信道插值则使用线性插值、二阶插值、低通插值、样条三次插值和时域插值来完成。时域插值是通过IDFT（离散傅里叶逆变换）传递到时域、补零并通过DFT（离散傅里叶变换）回到频域来获得的。另外，基于块类型导频布置的信道估计是通过在每个子信道处发送导频并将该估计用于特定数量的后续符号来执行的。我们还为所有子信道实现了决策反馈均衡器，然后是周期性块类型导频。我们通过测量误码率来比较所有方案的性能，其中 16QAM、QPSK、DQPSK 和 BPSK 作为调制方案，多径瑞利衰落和基于 AR 的衰落信道作为信道模型。
The channel estimation techniques for OFDM systems based on pilot arrangement are investigated. The channel estimation based on comb type pilot arrangement is studied through different algorithms for both estimating channel at pilot frequencies and interpolating the channel. The estimation of channel at pilot frequencies is based on LS and LMS while the channel interpolation is done using linear interpolation, second order interpolation, low-pass interpolation, spline cubic interpolation, and time domain interpolation. Time-domain interpolation is obtained by passing to time domain through IDFT (Inverse Discrete Fourier Transform), zero padding and going back to frequency domain through DFT (Discrete Fourier Transform). In addition, the channel estimation based on block type pilot arrangement is performed by sending pilots at every sub-channel and using this estimation for a specific number of following symbols. We have also implemented decision feedback equalizer for all sub-channels followed by periodic block-type pilots. We have compared the performances of all schemes by measuring bit error rate with 16QAM, QPSK, DQPSK and BPSK As modulation schemes, and multi-path Rayleigh fading and AR based fading channels as channel models.