基于互乘法窗函数的谐波分析方法

为了提高谐波分析的精度,加窗插值算法经常用用在非整周期和非同步采样的傅里叶变换中,以改善频谱泄露和栅栏效应。本文提出了一种互乘法窗函数的构造方法,并验证了基于互乘法窗函数的三谱线插值FFT的谐波高精度分析方法。以三种窗函数为例,根据每种窗函数在乘法窗的权值构造新的窗函数,分析新的窗函数的性能,将其应用到三插值FFT算法中。通过有/无噪声仿真实验说明:在三插值情况下,构造出的互乘法窗函数比常规窗函数在谐波参数测量中具有更高的精度。在实际工程中可根据需要选择所构造的窗函数。

An Algorithm for Harmonic Analysis based on Mutual-multiplication window function

Because the non-synchronous sampling and non-integral period truncation can result the spectrum leakage and fence effect , the window functions and interpolation algorithms have been used in the fast Fourier transform ( FFT) to improve the precision of harmonics analysis .This paper has introduced the construction method of mutual-multiplication window function .And we have verified an algorithm for harmonic high-precision analysis based on three-spectrum-line interpolation FFT .Three kinds of window functions were given various weights to construct new window function .Then the new window functions have been applied to the harmonics analysis method based on three -spectrum-line interpolation FFT .The simulation experiments show that constructing the mutual function relative to the conventional window function interpolation algorithm has a higher accuracy .We can choose them according to the per-formance of constructed window function in the practical engineering .