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Doppler Shift Estimation for Low Signal-Noise-Ratio Environment in Mobile Communication Systems

A novel iterative Doppler shift estimator is proposed in this letter for the Doppler shift estimation in very low signal- noise-ratio (SNR) environment. The proposed method exploits the logarithm envelope (LE) of the mobile propagation channel, and iteratively finds the minimum mean square error (MMSE) estimation of the Doppler shift. Extensive simulation results conducted under a wide range of the noise corruption clearly show that our proposed Doppler shift estimation method substantially outperforms all existing estimators.