A robust low complexity frequency domain iterative block DFE for SC-FDMA system

Recently, single-carrier frequency-division multiple access (SC-FDMA) has been adopted as the uplink transmission scheme in Third-Generation Partnership Project Long-Term Evolution (3GPP-LTE). In this paper, we propose a robust, suboptimum, low complexity frequency domain iterative block decision feedback equalization (FD-IBDFE) for SC-FDMA system. Based on the minimum mean square error (MMSE) criterion, we optimize the coefficients of the feedforward and feedback filters. Simulation results show that, at the first iteration, the proposed FD-IBDFE achieves above 3.0 dB performance improvement over MMSE FD linear equalization for QPSK, 8PSK and 16QAM modulations. Furthermore, it also shows that, with soft-decision feedback, our algorithm converges faster and gets better performance than that of high complexity time domain Exact-MMSE-LE turbo equalization.