Low-Complexity Iterative Carrier Synchronization for Short Packet Turbo Receiver

We consider the problem of carrier frequency and phase synchronization at low SNR without a training sequence for short packet transmission. A low-complexity iterative joint symbol timing and carrier synchronization algorithm making use of the extrinsic information from the soft-input soft-output (SISO) decoder is proposed. The non-data-aided (NDA) algorithms are used for initial synchronization. The simulation results show that the frequency offset estimation is the most critical problem in low SNR region. The proposed low-complexity algorithm can reach the ideal performance with perfect synchronization in the absence of frequency offset at very low SNR. When the frequency offset exists, the proposed algorithm can work effectively and improve the performance significantly.