A Frequency Estimator for a Real Single-tone Based on Modified Pisarenko Harmonic Decomposer and Lag-limited Correlation Expansion

A frequency estimator for a real single-tone is proposed, in which coarse frequency estimation is firstly got by using Pisarenko harmonic decomposer (PHD) with correlation lags 1 and 2. As the correlation of noise concentrates mainly on small lags, the frequency is re-estimated by PHD with correlation maximal lag k in the principal value interval of the arccosine function and with correlation lag 2k, which is determined by the coarse estimation, to decrease the influence of noise. The final frequency is obtained by adding to the re-estimated frequency a fine adjustment term, the closed-form of which is derived from Taylor’s series expansion of lag-limited correlation. Simulation experiments illustrate the performance improvement of the proposed estimator via comparison with several existing frequency estimators.