Polarity Correction-based Synchronization Algorithm for DSSS Communication

In spread spectrum systems, the performance of time synchronization determines the communication quality, whereas the existing algorithms do not consider the impact of the information symbols’ polarity on synchronization performance. Besides, the despreading operation is carried out at a low signal-to-noise ratio (SNR), and hence it requires a number of hardware resources for the existing algorithms to achieve high-precision time synchronization. In view of this, the paper proposes a spread spectrum synchronization algorithm based on polarity correction. Firstly, the mathematical model of spread spectrum transceivers is established. Next, the polarity of the first signal period is taken as the reference to correct the polarity of the subsequently received signals. Then, the spread spectrum signal after polarity correction is accumulated and correlated. Finally, the time synchronization and despreading operations are performed to recover the information sequence. Numerical simulations indicate that our algorithm can effectively improve the time synchronization accuracy and achieve effective signal reception under the scenarios with low SNRs at the cost of extremely few resource consumption.