基于相位差校正法的加Blackman-harris窗FFT算法与实现

Algorithm and Implementation of Increases Blackman-harris Window FFT Bbased on Phase Correction Mmethod

相位差校正法是连续两次加窗截断时域信号并进行两次FFT变换,然后利用其对应离散谱线的相位差校正出谱峰处的准确频率和相位的新校正方法,通过利用插值fft算法的窗谱函数公式还可以校正其幅值,用以解决离散频谱分析中由于不能做到同步采样带来的较大误差。由于加Blackman-harris窗函数的频谱泄漏影响小、计算精度高,所以本文采用加Blackman-harris窗截断。

The phase correction method is to cut off two consecutive windowed time domain signal and FFT transform twice, and then use the phase difference of corresponding discrete spectral calibration accuracy of the spectral peak at the newfrequency and phase correction method, through the use of fft window interpolation algorithm formula can also be corrected spectral function of its amplitude. To solve the discrete spectrum analysis can not be achieved due to large errors caused by synchronous sampling. As added Blackman-harris window function of spectral leakage of small and high precision. So this paper, plus Blackman- harris windowtruncated.