非同步采样信号频谱插值校正分析法

针对周期信号实际的非同步采样,提出一种频谱插值校正的分析法.经分析周期信号不同步采样时产生的频谱泄漏是由于截断信号与原始待分析信号的相位关系发生了变化.利用加窗插值的方法估计出该变化的相位,并利用估计结果构造出一相应的反相位函数,在时域上将这个反相位函数与由傅立叶反变换产生的离散序列相乘,得到新序列再通过一次傅立叶变换就可达到频谱校正的效果.分析、仿真和实验的结果验证了提出方法的有效性,表明所提出方法提高了不同步采样时周期信号频谱分析的精度.

Spectral Interpolated Compensation Analysis of Non-Coherent Sampling Signals

A new spectral interpolated compensation analysis method of periodic signals to compensate the spectral leakage caused by non-coherent sampling process is presented.Analysis of the non-coherent sampling process indicates that the frequency leakage is caused by the relative phase variations between the original and truncated signals.The change phase is estimated by window and interpolation algorithm,and then a phase compensation function can be built accordingly.By multiply this function and the data sequence from the IFFT of the truncated data sequence spectrum in the time domain,the spectral leakages can be compensated when the new data sequence is transformed into the frequency domain by the DFT.Analysis,simulation and experimental results show that the proposed method greatly improves the spectral analysis precision of the periodical signals under the non-coherent sampling conditions.