Modified Algorithm of Sinusoid Signal Frequency Estimation Based on Quinn and Aboutanios Iterative Algorithms

The problem of estimating the frequency of a complex signal is considered. Through analyzing the performance of the Quinn algorithm and Aboutanios iterative algorithm, when the frequency of signal is located in the central region of two neighboring quantized frequency in discrete Fourier transform (DFT), Quinn algorithm's precision is very high and its root-mean-square error (RMSE) is close to Cramer-Rao bound (CRB). Meanwhile, the variance of frequency estimated by the Aboutanios iterative algorithm is big. However, when the frequency is located in the vicinity of quantitative frequency point, the Quinn algorithm's accuracy is poor and Aboutanios iterative algorithm has high precision. In this paper, through combining the advantages of two kinds of algorithms and obtaining the correct interpolation direction by spectral shift in the vicinity of quantitative frequency point, there is a new comprehensive algorithm which has better computational efficiency and its RMSE is close to the CRB in the entire frequency estimation range.