Abstract: For the carrier synchronization in short burst communication system, a joint Rotational Periodogram Averaging (RPA) and demodulation soft information carrier estimation algorithm is proposed. First, the pilot sequence is rotated with different frequency offsets, and the coarse carrier estimation is carried out with periodogram averaging method. Then, further fine estimation is done by stepwise search. The precise carrier synchronization parameters are obtained based on the criterion of Maximum-Mean-Square Soft Output (M2S2O). Simulation results show that the proposed algorithm with short pilots and lower complexity can achieve a BER performance which is very near that of the optimal coherent demodulation and eliminate large carrier offsets as much as plus and minus half of the data rate. When Bit Error Rate (BER) is in the region of 10-2~10-4, the Signal-to-Noise Ratio (SNR) degradation is within 0.3 dB.