Intrinsic Interference Elimination for Preamble-Based Channel Estimation in FBMC Systems

In the recent fifth generation (5G) research, filter bank multi-carrier (FBMC) technique is one of the competitive substitutes to orthogonal frequency division multiplexing (OFDM). The most fascinating features of FBMC are theoretically higher spectral efficiency and extremely low out-of- band radiation by removing cyclic prefix (CP) and using well-localized pulse shape. However, conventional OFDM channel estimation (CE) methods cannot be directly applied to FBMC, because it exists the intrinsic inter-carrier/inter-symbol interference resulting in performance degradation. This paper presents a new preamble-based CE method using two different FBMC symbols to transmit the preamble sequences and their copy, respectively. Consequently, the intrinsic interference of the two received preambles can be eliminated by combining them. Simulation results indicate that the new method obtains the almost same CE performance as that of CP-OFDM in multi-path fading channel. In addition, the preamble power of the new method is significantly lower than that of other existing methods in FBMC.