Time reversal time-domain synchronisation orthogonal frequency division multiplexing over multipath fading channels with significant tap delays

Time-reversed orthogonal frequency division multiplexing (TR-OFDM) has recently received attention as a promising spectral efficient scheme for single-input multiple-output communications over time-dispersive fading channels. For TR-OFDM, passive time reversal processing is used as a simple means for channel time dispersion reduction. In particular, pseudorandom noise (PN)-sequence padding timedomain synchronisation OFDM (TDS-OFDM) transmission scheme has been reported as an appealing alternative to the traditional cyclic prefix (CP) OFDM technology as it can provide significant improvement in the spectrum efficiency. In this study, a new correlation based coder for inter-block and inter-symbol interference removing in time-reversed TDS-OFDM, which is denoted TR-TDS-OFDM briefly is proposed. Such a coder is, then, tested for multipath channels with significant tap delays. A Zadoff–Chu sequence with perfect autocorrelation property is adopted as a training sequence (TS) for a TDS-OFDM system. Simulation results show that, by using TR-TDS-OFDM with correlation- based coder, a TS with length shorter than channel order can be used without introducing notable inter-block interference. The other merits of the proposed design are also supported by both theoretical analysis and numerical simulations.