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Performance Improvement of Low Complexity LS Channel Estimation for OFDM in Fast Time Varying Channels  

Lim, Dong-Min (Gyeongsang National University)
Publication Information
Journal of the Institute of Electronics Engineers of Korea TC / v.49, no.8, 2012 , pp. 25-32 More about this Journal
Abstract
In this paper, we propose a method for improving the performance of low complexity LS channel estimation for OFDM in fast time varying channels. The CE-BEM channel model used for the low complexity LS channel estimation has a problem on its own and deteriorates channel estimation performance. In this paper, we first use time domain windowing in order to remove the effect of ICI caused by data symbols. Then samples are taken from the results of the LS channel estimation and the effects of the windowing are removed from them. For resolving the defect of CE-BEM, the channel responses are recovered by interpolating the resultant samples with DPSS employed as basis functions the characteristics of which is well matched to the time variation of the channel. Computer simulations show that the proposed channel estimation method gives rise to performance improvement over conventional methods especially when channel variation is very fast and confirm that not only which type of functions is selected for the basis but how many functions are used for the basis is another key factor to performance improvement.
Keywords
OFDM; time varying channel; LS channel estimation; BEM channel model; interpolation;
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Times Cited By KSCI : 2  (Citation Analysis)
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