中文说明：
数字信号处理 传统的宽带信号中抑制正弦干扰的方法是采用陷波器(notch filter),为此我们需要精确知道干扰正弦的频率.然而当干扰正弦频率是缓慢变化时,且选频率特性要求十分尖锐时,则最好采用自适应噪声抵消的方法.下图是用一个二阶FIR的LMS自适应滤波器消除正弦干扰的一个方案。
English Description：
In digital signal processing, notch filter is used to suppress sinusoidal interference in traditional wideband signal, so we need to know the frequency of the interference sinusoid accurately. However, when the frequency of the interference sinusoid changes slowly and the frequency selection characteristic is very sharp, The figure below shows a scheme of eliminating sinusoidal interference with a second-order fir LMS adaptive filter.