Accurate Frequency Estimation by Using Three-Point Interpolated Discrete Fourier Transform Based on Rectangular Window
Accurate Frequency Estimation by Using Three-Point Interpolated Discrete Fourier Transform Based on Rectangular Window
复制标题
基于矩形窗的三点插值离散傅里叶变换精确频率估计
DOI：
10.1109/tii.2020.2981542
复制
发表时间：
2021-01-01
影响因子：
12.3
通讯作者：
Li, Guoqing
中科院分区：
文献类型：
--
作者：
Wang, Kai;Wen, He;Li, Guoqing
加窗插值离散傅里叶变换（DFT）是一种有效的频率估计方法，可以有效地解决频谱泄漏和栅栏效应。当采集的正弦波周期数较少时，负频率的长距离频谱泄漏是导致精度低的主要原因。本文提出了一种基于矩形窗的三点插值DFT频率估计器。该插值算法采用正负频点的频谱叠加来消除近、远距离频谱泄漏。由于所采用的矩形窗在所有窗中具有最小的主瓣宽度或最小的等效噪声带宽，因此可以减小白色噪声对频率估计的影响。仿真和实验结果表明，该方法优于现有的加窗插值DFT算法。
Windowed interpolated discrete Fourier transform (DFT) has been well-studied to deal with the spectral leakage and picket fence effects in frequency estimation. When the number of acquired sine-wave cycles is small, the long-range spectral leakage of the negative frequency is the main cause of low accuracy. In this article, a novel frequency estimator using three-point interpolated DFT based on rectangular window is proposed. The spectral superposition of positive and negative frequencies is adopted in the proposed interpolation algorithm to remove both short- and long-range spectral leakage. The influence of white noise on frequency estimation can be reduced because the adopted rectangular window has the narrowest mainlobe width or the smallest equivalent noise bandwidth among all windows. Simulation and experimental results confirm that the proposed method outperforms existing windowed interpolated DFT algorithms.