A maximum likelihood Doppler estimation algorithm for underwater acoustic communication

The present paper aims to provide an efficient Doppler estimation algorithm for the underwater acoustic communication. A maximum likelihood estimation (MLE) algorithm was derived from frequency offset. The MLE algorithm proposed in this paper estimated Doppler shifts by DFT or FFT, where a well-designed training symbol was used. Several pilot tones constituted the training symbol. The simulation results show that our MLE algorithm is nearly unbiased. And we also present a reduced complexity algorithm, whose performance is very close to the MLE algorithm.