改进的双速率同步采样法及其傅里叶变换

针对现有的双速率同步采样序列离散傅里叶变换(DFT)的算法是一个经验公式和计算量大的缺陷,提出了一种改进的双速率同步采样法.改进的采样法采用传统的采样间隔补偿方法以平抑对周期信号采样所产生的周期误差,将所有的采样点按时间顺序划分成点数相同的前后两组,对两段中对应点的采样间隔分别给以相同的补偿,将双速率采样问题归结成均匀采样问题,并利用均匀采样的基本理论,导出改进的双速率采样序列DFT的算法.分析结果表明,与传统补偿方法相比,改进的采样法不仅能有效地抑制采样的周期误差,而且DFT算法的乘法计算量减少了一半.适用于周期信号的电参数测量与频谱分析.

Improved double-speed synchronous sampling method and Fourier transform

Considering the existing algorithm model of discrete Fourier transform (DFT) to be an empirical formula involving much calculation, a kind of new double-speed synchronous sampling method and DFT model were proposed under condition of double-speed synchronous sampling. The method adopted a traditional sampling compensated method. All sampling points were equally divided into two groups with the same compensation of corresponding points in order of time, and equal sampling interval of corresponding points was obtained. Utilizing the basic theories of uniform sampling, the algorithm model of the improved double-speed synchronous sampling was derived out. Analytic results show that compared with the original method, the model halves the original calculating amount of multiplication, and the proposed method can decrease effectively the sampling periodic error and be applied to electric parameter measurement of periodic signal and for analysis of frequency spectrum.