基于滤波器组传输的移位正交滤波器的实现方法

Implementation Method for Shift Orthogonal Filter in Filter-Bank Based Transmission

针对滤波器组传输的广义多载波频分多址系统,提出一种基于DFT插值的移位正交滤波器的实现方法。现有设计的具有移位正交性的原型滤波器一般直接产生,例如根升余弦滤波器,不具有通用性。文中所提设计方法,首先根据原始的某种移位正交低阶滤波器,通过DFT变换至频域,在频域进行补零插值,再通过IDFT变换至时域,可得到一种基于DFT插值的高阶滤波器,且该滤波器保持移位正交性。理论分析和仿真结果表明,该方法设计的移位正交滤波器更简单、更通用,非常适合于滤波器组传输系统。

A DFT-based interpolation shift orthogonal filter implementation method is proposed for the generalized multi-carrier frequency division multiple access systems based on filter bank.As the current shift orthogonal filters,such as root cosine pulse filters are mostly special designed,which are not universal.In this paper,the original low-order shift orthogonal filter is transformed from the time domain to the frequency domain by DFT.Then the interpolation is performed and is transformed back to the time domain by IDFT.Finally,a kind of high-order DFT-based interpolation filters is obtained,which keeps the shift orthogonality.Theoretical analysis and simulation results show that the proposed method is simpler and more universal,thus it is suitable for the transmission systems based on the filter bank.