Fast Fourier transform harmonic analysis based on nine terms minimum side-lobe cosine-sum window

Since it´s difficult to do synchronous sampling when making the signal sampling, the spectral leakage and fence effect will occur during fast Fourier transform (FFT) processing, which leads to greater measurement errors. To solve these problems, this paper proposes an interpolation FFT algorithm based on the nine terms cosine-sum window with minimum side-lobe and deduces the correction formula of this algorithm using the dual interpolated theory. Compare the measurement result of this algorithm by simulation with the measurement results of interpolation algorithm based on the Hanning window `Blackman-Harris window´ Nuttall window, which verifies that this algorithm is more accurate at measurement and has the actual application value.