关键词: 频率估计, 延时互相关, 非整周期采样, 正弦信号, 误差校正

Abstract: To improve the frequency estimation precision of the sampled signals with non-integer period, a frequency estimation method for sinusoidal signal based on delay cross-correlation is proposed. Firstly, the sampled signal and its equal length delay signal are truncated. Secondly, the two segment signals are calculated by cross-correlation, and the error correction signal with non error term is constructed. Then, the coarse frequency estimation of the error correction signal is obtained, and the reference signal is generated. Finally, the error function is constructed according to the Cauchy Schwarz inequality, and the fine frequency estimation value is obtained by minimizing the error function. The results of simulation experiments indicate that the proposed method effectively reduces the influence of the non-integer period sampling, and improves the accuracy of frequency estimation, which is better than the frequency estimation method based on autocorrelation under the same conditions. The root mean square errors of the frequency estimation value are closer to the Cramer-Rao lower bound.

Key words: frequency estimation, delay cross-correlation, non-integer period sampling, sinusoidal signal, error correction