窗函数在信号处理中的应用

在进行快速傅里叶变换时,对信号进行截断会产生频谱泄漏现象。为减小频谱泄漏的影响,以理论分析窗函数为基础,利用Matlab作为辅助工具绘出汉宁窗、汉明窗、矩形窗、三角窗和布拉克曼窗的时域幅度与频域幅度曲线,分析了频谱泄漏的原理以及各窗函数的特点和性能,提出了在对信号进行截断时,如何通过选择合适的窗函数来减小频谱泄漏对信号分析的影响。用Matlab软件对某一信号进行加窗仿真实验,结果表明:汉宁窗最适合此实验信号,验证了选择合适的窗函数的重要性.

Application of Window Function in Signal Processing

The signal is intercepted in the process of FFT, which will cause spectrum leakage. In order to reduce the effect of spectrum leakage, based on theoretical analysis of window function,using Matlab as a tool to make time domain amplitude and frequency amplitude curve of the Hanning window, Hamming window, rectangular window, triangular window and Blackman window,this paper analyzes the principle of spectrum leakage and the features and functions of the window function, chooses the appropriate window function to cut down the spectrum leakage which is provided. A simulation experiment that window function is added to a singal make full use of Matlab software,the Hanning window is most suitable for the signal in the experiment, verifying the importance of choosing the appropriate window function.