MLSE and MMSE subchannel equalization for filter bank based multicarrier systems: Coded and uncoded results

Abstract

Filter Bank Based Multicarrier (FBMC) systems appears to be the best choice to replace Cyclic Prefix (CP) based Orthogonal Frequency Division Multiplexing (OFDM) as the physical layer of future wireless communications devices. Some equalizer solutions for FBMC systems already exist. Among them, the equalizers minimizing the mean square error (MMSE) criterion show the best trade-off between complexity and performance. In this work we evaluate the uncoded BER performance of FBMC systems with two kinds of receivers: the per-subchannel MMSE Linear Equalizer (LE) and a maximum likelihood sequence estimator (MLSE). Moreover, we compare the coded and uncoded BER of FBMC with CP-OFDM in a configuration where both systems have the same spectral efficiency. From our results we can conclude that the MMSE LE achieves a satisfactory performance compared to the MLSE with a much lower computational complexity. We also show that the FBMC scheme reduces the energy per bit by 2.5 dB compared to CP-OFDM under the same spectral efficiency.