基于DFT-FB改进的F-OFDM方案

通过对滤波OFDM(filtered-OFDM,F-OFDM)的研究,针对F-OFDM使用较长的子带滤波器降低带外泄漏(out-of-band emission,OOBE)而导致系统实现复杂度较高的问题,基于滤波器组(filter bank)的多相网络(poly phase network,PPN)实现降低复杂度和对每一个子载波进行独立的滤波降低OOBE的思想,提出了使用子载波滤波的滤波器组技术对F-OFDM的改进方案,实现对每个子载波的滤波处理.给出了改进方案的系统结构图并分析了系统原理,通过对改进方案系统的分析及带宽效率和系统实现复杂度的推理计算,得到改进方案可以达到与F-OFDM相同的带宽效率,且在相同的功率谱密度时,改进方案的实现复杂度比F-OFDM系统的低.仿真结果表明,相较于F-OFDM,改进方案不仅可以优化系统处理业务的灵活性,而且在AWGN(additive white Gaussian noise)信道和衰落信道下,在传输性能和抗信道衰落能力方面,也优于F-OFDM系统.

Improved F-OFDM scheme based on DFT-FB

Due to using long subband filters to reduce the out-of-band emission(OOBE), the complexity of filtered-OFDM(F-OFDM)is very high. In order to solve this problem, based on the thoughts of filter bank processing, i.e. using polyphase network(PPN) to reduce the system complexity and filtering in each subcarrier to lower OOBE, this paper proposes subcarrier filtering technology of filter bank to improve F-OFDM. Compared with F-OFDM, the proposed scheme can obtain the same bandwidth efficiency and less implementation complexity. The simulation results also show that the proposed scheme can not only optimize the flexibility of system, but also improve the transmission performance and anti channel fading ability in AWGN(additive white Gaussian noise) channel and fading channel.