An improved channel estimation method based on the correlation of preambles in FBMC/OQAM systems

Filter bank multicarrier transmission with offset QAM (FBMC/OQAM) is recognized as one of candidates for the next generation of multi-carrier modulation scheme due to its high spectral efficiency and extremely low out-of-band attenuation. However, channel estimation (CE) performance may be seriously deteriorated by the intrinsic interference in practice. Because the correlations of preambles at the receiver may not be taken into account for traditional methods, which are recognized as inter-symbol interference. This paper proposes an improved preamble-based CE method, which has lower preamble power and higher time efficiency, and a CE algorithm using correlation between adjacent subcarriers is introduced to improve performances further. Finally, the CE algorithm with correlations between adjacent K subcarriers is deduced. Simulation results show that the proposed scheme has lower BER and preamble power, compared to the traditional methods.