A multi-carrier detection algorithm for OFDM systems without guard time

A new demodulation algorithm is proposed for orthogonal frequency division multiplexing (OFDM) systems without guard time (GT) to mitigate inter-symbol interference (ISI) and inter-carrier interference (ICI) introduced by multipath channels. The proposed algorithm is analogous to the multiuser detection (MUD) technique, successive interference cancellation based on decision feedback (SIC-DF), for synchronous DS-CDMA systems, hence it is named SIC-DF multicarrier detection (MCD) algorithm. Theoretical analysis and simulation results demonstrate that SIC-DF MCD can efficiently combat ISI and ICI for OFDM systems without GT by using joint multi-carrier time domain equalization instead of one-tap frequency domain equalization at the cost of reasonable complexity increase, and moreover, with SIC-DF MCD algorithm, an OFDM system without GT can offer lower uncoded bit error rate than the conventional OFDM system with GT.