基于滤波多音改进的F-OFDM方案

摘要

For the strict timing synchronization requirement among the subbands of the filtered-OFDM(F-OFDM) system,a modified scheme is proposed to realize the F-OFDM system through the filtered multi-tone (FMT) modulation technique based on the theory of filter banks.By the subcarrier level filtering pro-cessing based on the filter banks structure and adopting FMT modulation with non-overlapping carrier spectrum,the improved scheme named M-FB relieves the strict timing synchronization requirements. The simulation results show that the proposed scheme is capable of decreasing the out-of-band emission (OOBE) to -65 dB further,and performs well in anti-carrier frequency offset (CFO) performance in the case of additive white Gaussian noise (AWGN) channel or Rayleigh fading channel. Compared with the classical implementation of F-OFDM,the proposed scheme has lower computational complexity.%针对滤波OFDM(F-OFDM)系统对子带内定时同步要求严格的问题,提出了一种基于滤波器组的滤波多音(FMT)调制技术来实现F-OFDM的改进方案.通过滤波器组结构实现子载波级的滤波处理,采用载波频谱不重叠的FMT调制,改进方案降低了子带内严格的定时同步要求.仿真结果表明,所提方案可进一步将带外发射(OOBE)抑制到-65 dB深度,且在加性高斯白噪声(AWGN)信道和瑞利衰落信道下,具有较好的抗载波频率偏移(CFO)性能.相比于F-OFDM的直接实现,改进方案具有更低的运算复杂度.