基于系数查找表的全相位FIR自适应陷波器

All-phase FIR Adaptive Notch Filter Based on Coefficient Look-up Table

本文分析了全相位DFT数字滤波器优良的频域传输特性,进而提出基于滤波器系数抽取查找表的全相位自适应陷波算法。该算法以陷波器输出信号的能量作为判断依据选择抽头系数,省去了传统频域FIR滤波器的FFT步骤,因而计算量小,而且变传统闭环控制为开环控制,因而收敛快,并可把频率设置点上的干扰完全陷波到0。因而相比于传统IIR和FIR陷波器,性能有了很大提高。

This paper analyzed the excellent transfer property of all-phase DFT digital filter and presented the all-phase adaptive notch algorithm based on the filter coefficient decimation look-up table. This algorithm introduced the filterg output power as the warrant to choose coefficient, namely that the conventional step of FFT is omitted and the computation complexity is reduced. Replacing the conventional close loop control with open loop control leads to a faster convergence. In addition, the component of disturbance at the frequency setting point can be completely trapped into zero. Contrast to the conventional IIR and FIR notch filter, the performance of all-phase notch filter is enhanced.