正弦波频率快速估计方法

Fast Frequency Estimation of Single Tone

研究了正弦波ＤＦＴ系数的结构，通过ＤＦＴ系数的相位信息，得到了一种快速频率估计算法。经过二次ＤＦＴ运算消除了初相的影响，成功地解决了相位模糊问题。仿真结果显示，本算法有较高的精度，在ＲＳＮ＝６０ｄＢ条件下，估计误差约为ＤＦＴ的１／１０，而计算量仅为两次ＦＦＴ。

The structure of the DFT coefficients of a single tone is analysed. A new accurate frequency estimator for a single tone is proposed by using the phase information of the DFT coeffients. The original phase of the single tone is shifted by using twice DFT. The vague of phase is corrected succussfuly. The simulation results indicate that the error of this approach is one-tenth of the DFT estimator only at RSN=6 dB. The computation of this approach is twice as FFT.