FBMC/OQAM系统基于前导码相关的信道估计改进方法

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

滤波器组多载波/正交幅度调制(FBMC/OQAM)作为未来通信系统多载波调制候选方案,具有高频谱效率和极低的带外失真,但在实际应用中存在固有干扰,会严重恶化信道估计的性能.提出了一种改进的基于前导码的信道估计方法,此方法降低了前导码功率,提高了信号的时间效率.在此基础上,通过利用相邻子载波间相关性来进一步提高信道估计性能,因此,采用了具有相邻K个子载波之间相关性的信道估计方法.仿真结果表明:与传统方法相比,提出的改进信道估计算法具有较低的前导码功率和较好的BER性能.

Filter Bank Multi-Carrier transmission with Offset QAM(FBMC/OQAM)is recognized as one of the candidates for the next generation of multi-carrier modulation schemes,due to its high spectral efficiency and extremely low out-of-band distortion.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 Ksubcarriers is deduced.Simulation results show that the proposed scheme has lower BER and preamble power,compared to the traditional methods.