A T/2 fractionally-spaced sparse complete feedback equalizer scheme is proposed to avoid the performance deterioration caused by symbol timing error in the receiver, which is a generalized version of the previously proposed Complete Feedback Equalizer (CFE). The performance of the scheme is analyzed based on minimum mean square error (MMSE) criterion, and the MMSE performance is proved to be the same as that of the Decision Feedback Equalizer (DFE). The scheme also effectively exploits the sparseness of the multi-path channels with large delay spread and reduces the complexity of the equalizer with small performance degradation. Theoretical analysis and computer simulations over field measured wireless channel show that the scheme performs better than symbol-spaced CFE and T/2 fractionally-spaced DFE.
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