A low complexity decoding scheme of STFBC MIMO-OFDM system

Multiple transmit and receive antennas are used to form multiple-input multiple-output (MIMO) channels to increase the capacity and data rate of any wireless system. MIMO is combined with orthogonal frequency division multiplexing (OFDM) to mitigate inter-symbol interference (ISI). In this paper, a high rate space time frequency block code (STFBC) is presented with an approach different from algebraic codes to achieve code rate M_T with full diversity of M_T M_R M_b L. The received STF coded MIMO-OFDM signals has high decoder complexity. Computational complexity of decoder and latency induced by it can be resolved by employing sphere decoder (SD) and array processing decoder. The performance of presented STF code is analyzed and verified by simulation results. Bit error rate (BER) performance expressions for STFBC MIMO-OFDM systems are derived and evaluated for frequency selective block fading channels with MPSK constellations.