基于零相位数字滤波器的边界问题的分析

Analysis of the boundary problems based on zero-phase digital filter

在分析传统的两种零相位数字滤波器设计FRR(Forward filter,Reverse filter,Reverse output)和RRF(Reverse filter,Reverse filter,Forward output)原理和方法的基础上,将FRR与RRF结合,对零相位数字滤波器的设计方法进行改进;通过仿真实验将传统的两种设计方法与改进的设计方法进行了结果对比和验证。结果表明结合法可以使数字信号处理中零相位滤波器存在的边界失真问题得到很好的解决,在高速铁路轨道不平顺信号的处理中得到了很好的应用。

General differential filter always has two serious problems, which are phase-shift and boundary waveform distortion. Traditional zero phase digital filter can only improve the phase-shift, but can＇t overcome the boundary distortion. To improve this shortcoming, two traditional methods are analyzed,which are FRR（Forward filter,Reverse filter,Reverse output）and RRF（Reverse filter,Reverse filter,Forward output）. Based on the analysis of the principles and methods of these two design methods, combine the FRR and RRF together and give the demonstration on the simulation experiments about the three methods, solving the problem of boundary distortion in digital signal processing. The result shows that combination method is a good method to resolve the existing boundary issues. Finally, describes the application on the high-speed railway track irregularity signal processing.