一种基于DFT的LTE上行信道估计改进方案.doc

一种基于DFT的LTE上行信道估计改进方案.docImproved DFT-based Channel Estimation for LTE Uplink
Zhou Liying, Wang Weidong
(School of Electronic Engineering, Beijng University of Posts and Telecommunications, Beijing
J J J 100876) J
Abstract: Discrete Fourier transform (DFT) based channel estimation (CE) has been widely studied for its balance between performance and complexity. Considering the practical situation, there are two main problems. One is insufficient noise suppression due to unknown channel statistic and the other is channel energy leakage caused by limited band allocation and virtual subcarriers. As a result, the conventional DFT-based CE suffers performance degradation. In this paper, an improved DFT-based CE method is addressed for Long-Term Evolution (LTE) uplink to combat these two problems with low complexity and no need for prior knowledge. A decimation of channel impulse response (CIR) based on tap-tuned threshold and symmetrical extension signal processing is proposed for efficient noise elimination with less channel energy loss. Simulation results manifest that the proposed method can improve normalized mean square error (MSE) performance of the CE module through different comparisons. Besides, the accuracy of noise variance estimation is also increased.
Key words: mobile communication; LTE; channel estimation; channel impulse response; threshold-based selection; energy leakage
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