Time-Delay Estimation for single-frequency pulse signals based on differential Maximum Likelihood estimation method and DTFT

A hybrid Time-Delay Estimation (TDE) method for single-frequency pulse signals is proposed. This method combines differential Maximum Likelihood (ML) TDE and TDE using the phase difference of the DTFT (Discrete-Time Fourier Transform) of the received signals. It first estimates the coarse delay of the pulse using ML TDE, and then truncates the section of the pulse and use DTFT-based TDE to estimate the accurate time delay. The minimum achievable delay variance is derived. The performance of this method is given for different signal-to-noise ratios.