Tentative Decision Based Low Complexity Equalization for OFDM Systems with Insufficient Cyclic Prefix

In this paper, a new low complexity equalization scheme is presented to mitigate inter-symbol interference (ISI) and inter-carrier interference (ICI) for orthogonal frequency division multiplexing (OFDM) systems with insufficient cyclic prefix (CP). After conventional decision-feedback ISI cancellation, the proposed scheme cancels ICI in frequency domain. By using tentative hard decisions, the new scheme avoids the nondiagonal matrix inversion in conventional zero-forcing (ZF) decision feedback equalizer (DFE). It is shown that while offering the advantage of significantly lower computational complexity the proposed scheme maintains approximately the same performance as conventional ZF-DFE method