Joint channel and frequency offset estimators for frequency-flat fast fading channels

In this paper, two joint data-aided channel and frequency offset estimators are proposed for frequency-flat fast fading channels. The proposed estimators are based on cubic spline approximation and a two stage frequency estimation using a fast Fourier transform-based coarse search and dichotomous fine search. The first estimator relies on the Bayesian approach and by exploiting prior channel statistics can provide a high performance. The second estimator, with a slightly lower accuracy, can operate when the prior statistics are unknown. These estimators are examined for Rayleigh fading channels. They achieve a high accuracy performance over a wide range of signal to noise ratio, for different Doppler frequencies and throughout all the frequency acquisition range.