Single-carrier and multi-carrier space-time block coded transmissions over doubly selective fading channels

We propose a multi-stage successive interference cancellation (SIC) receiver for arbitrary linear space-time block codes (STBCs) over general time-frequency selective fading channels with single-carrier (SC) transmissions. The proposed receiver adopts the SIC approach to handle inter-symbol interference (ISI) owing to multipath propagation. Simulation results show that the proposed receiver outperforms the OFDM system after a few iterations in the BER range 10^-3 to 10^-5. We also propose a diversity enhancement space-time signalling scheme for four transmit antennas with an increased diversity order. Simulation results show that the proposed diversity enhancement scheme outperforms the OFDM system even at the first iteration