A Pseudo-Code-Aided Carrier Synchronization Method for THz Communication System

We introduce a pilot-aided carrier synchronization method for the THz communication system in inter-satellite transmission links. By adding low-power low-speed pseudo- code pilot, which has good correlation property and robust noise resistance, to the high-speed data signal, we can easily extract the frequency offset information through processing the low-speed pilot. Compared to the traditional Costas loop method, the proposed method reduces the computational complexity by $10^{6}$ times, ensures a large estimation range of the frequency offset and achieves more accurate estimation value. However, the proposed method suffers from a loss of 0.11dB at the bit error rate (BER) of $10^{-5}$ when the pilot power is lower than the data signal power by 26dB. Considering the processing complexity is attached most importance in such real-time large-capacity communication occasions, we believe it applicable to use the sacrifice of a little reliability for the significant reduction in complexity.