A joint rotational periodogram averaging and demodulation soft information carrier synchronization algorithm

In short burst communication system, a joint rotational periodogram averaging (RPA) and demodulation soft information carrier estimation algorithm is proposed in this paper. Firstly, the coarse carrier estimation is carried out with periodogram averaging method after that the pilot sequence is rotated with different frequency offsets. Then, further fine carrier estimation is done by stepwise searching 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 an excellent Bit Error Rate (BER) performance and eliminate large carrier offsets as much as half of the symbol rate. When BER is in the region of 10^-2~10^-5, Signal-to-Noise (SNR) degradation is within 0.3dB.