常用窗函数
I’mNVH
窗函数通过对信号进行加权,以减少信号的旁瓣泄露和平滑信号的边缘,从而提高信号的频谱分辨率。窗函数的选择取决于所需应用的特性,如矩形窗、汉宁窗、汉明窗和布莱克曼窗等,每种窗都有其特定的频率响应和旁瓣衰减特性。本文将介绍几种常见窗函数的计算公式和时域频域曲线,并给出其基本的评价指标。
Rectangle(矩形窗)
$$w(n)=1, 0\leq n\leq N$$ $N$ is the length of window.
Hanning(汉宁窗)
$$w(n)=0.5(1-cos(2\pi\frac{n}{N-1})), 0\leq n\leq N$$ $N$ is the length of window.
FlatTop(平顶窗)
$$w(n)=\frac{1-1.93cos(2{\pi}\frac{n}{N-1})+1.29cos(4{\pi}\frac{n}{N-1})-0.388cos(6{\pi}\frac{n}{N-1})+0.0322cos(8{\pi}\frac{n}{N-1})}{4.634}, 0\leq n\leq N$$ $N$ is the length of window.
BlackHarris
$$w(n)=0.35875-0.48829cos(2\pi\frac{n}{N-1})+0.14128cos(4\pi\frac{n}{N-1})-0.01168cos(6\pi\frac{n}{N-1}), 0\leq n\leq N$$ $N$ is the length of window.
KaiserBessel
$$w(n)=0.40243-0.49804cos(2\pi\frac{n}{N-1})+0.09831cos(4\pi\frac{n}{N-1})-0.00122cos(6\pi\frac{n}{N-1}), 0\leq n\leq N$$ $N$ is the length of window.