The Code-Aided FEPE Algorithm for Joint Frequency and Phase Estimation at Low SNR

Estimation of carrier parameters is of paramount importance in digital communications so as to satisfy the requirements in terms of availability and throughput. This is particularly challenging for systems operated in burst mode, where carrier frequency and phase estimates must be computed for each packet or frame. In this context, the reliability of frequency estimates might be a major problem, in case they are provided under low SNR conditions. Enlarging the observation length is basically possible, but this has to be paid by an increase of complexity and redundancy. In order to avoid this dilemma, an algorithm for frequency estimation through phase estimation (FEPE) has been suggested in the technical literature, which is both simple and powerful. Motivated by this approach, we propose that the operation of the FEPE module is closely linked to that of a duo-binary turbo decoder, establishing this way the code-aided joint recovery of carrier and data. Appropriately selected simulation results confirm the utility of the introduced concept.