Abstract
A simple channel estimator for space-time coded orthogonal frequency division multiplexing (OFDM) systems in rapid fading channels is proposed. The channels at the training bauds are estimated using the EM (expectation-maximization) algorithm, while the channels at the data bauds are estimated based on the method for modelling the time-varying channel as the linear combination of several time-invariant “Doppler channels”. Computer simulations showed that this estimator outperforms the decision-directed tracking in rapid fading channels and that the performance of this method can be improved by iteration.
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Project supported by the National Hi-Tech Research & Development Program (863) of China (No. 2001AA121031) and the National Natural Science Foundation of China (No. 60272079)
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Shu-wei, S., Han-wen, L. & Wen-tao, S. A simple channel estimator for space-time coded OFDM systems in rapid fading channels. J. Zheijang Univ.-Sci. 5, 45–49 (2004). https://doi.org/10.1631/BF02839311
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DOI: https://doi.org/10.1631/BF02839311