FIR数字低通滤波器工频干扰抑制能力的提高

用Matlab按窗函数法设计较低阶数的FIR数字低通滤波器时，其工频干扰抑制能力一般需要优化。通过对其幅频特性的研究，发现适当调整截止频率可显著提高其工频干扰抑制能力。设计了Matlab程序，用户只需输入一些基本要求，即可获得具有高工频干扰抑制能力的FIR数字低通滤波器。

Improving the power-line-interference rejecting ability of FIR low-pass digital filter

When designing FIR low-pass digital filters whose orders are not high enough with Matlab using the window functions method, their power-line-interference rejecting abilities usually need optimizations. By inspecting their magnitude-frequency characteristics,it is found that the rejecting abilities can be improved by adjusting appropriately their cut-off frequencies. And a Matlab program is developed to do this automatically. Using the program, after inputting only a few basic required parameters, one can obtain a FIR low-pass digital filter with high power-lineinterference rejecting ability.