基于双相移组合全相位法的FIR陷波器设计

FIR notch filter design based on double phase-shift combination all-phase method

提出新的双相移组合全相位设计FIR陷波器算法。根据单窗情况下全相位滤波的3个重要性质,利用两个互为对称的陷波频率向量用全相位方法设计出两个子滤波器,并构造两个互为共轭的相移向量分别对两个子滤波器进行相移,再将两者进行组合即可生成陷波器。通过理论证明:陷波器的设计可通过代入一简单公式来实现,计算复杂度非常低。实验表明:通过改变相移参数值,在任意频率点上陷波器的衰减值可达-330dB。

A novel notch filter design algorithm-all-phase method based on double phase-shift combination is preseated. Based on three important properties of all-phase filtering under single window, all-phase method is utilized to design two sub filters from two symmetric notch frequency vectors, And two conjugate phase-shift vectors are applied on these two sub filters respectively. Thus a notch filter can be constructed by combining these two filters. Moreover, theoretic deduction proves that the proposed notch filter can also be formed by substituting a simple formula, which means computation complexity is greatly reduced. Experiments prove that the notch attenuation value can reach -330 dB at arbitrary frequency by adjusting phase-shift parameter.