频谱分析中用于相位和频率校正的相位差校正法

提出了一种对连续时域信号分前后两段作傅里叶变换,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——相位差校正法,通过窗谱函数的公式还可以校正其幅值,以解决离散频谱分析中由于谱峰谱线没有对正峰顶时所带来的较大误差。该方法原理简单,通用性好,运算速度快,校正精度高,可以在不知道窗谱函数表达式的情况下,直接用其相位差进行求解。仿真研究表明,对单频率成分的频率、相位、幅值进行校正,频率误差小于0.0002个频率分辨率,相位误差小于0.1 度,幅值误差小于0.02% 。

A Phase Difference Correction Method for Phase and Frequency Correction in Spectral Analysis

A new method, phase difference correction method, is presented to correct the frequency and phase by separating the continuous time domain signal into two segments and making FFT respectively, then correcting by use of the phase difference of corresponding discrete spectral lines. Furthermore, the amplitude can be rectified using the formula of window function. This method, with its adaptability, high speed and accuracy, is theoretically simple. It resolves the frequency by means of phase difference directly without the formula of window function. The simulation shows that the single component frequency, phase and amplitude of harmonic signal can be corrected satisfactorily, with frequency error less than error less than 0.0002 frequency resolution, phase error less than 0.1 degree and amplitude error less than 0.0002.