A new method for PN code synchronization in the direct sequence spread spectrum communication systems

Pseudo-Noise (PN) code synchronization is of crucial for receiver in direct sequence spread spectrum (DSSS) communication. What's more, acquisition and tracking are two important parts of the synchronization process. To meet the need of a lower power consumption and higher performance, there is a trend to design the digital match filter by using the field programmable gate array (FPGA) or the application specific integrated circuit (ASIC). This paper proposes a new PN code synchronization method based on FPGA and software radio technology. The adaptive threshold detection technology is first used at the acquisition stage to realize the relative judgment. Then the phase demodulation loop based on 1/2 lead-lag code is introduced to the tracking stage, which can guarantee the strictly synchronization between the local PN code and the received code. Simulation and actual experiment results validate the performance of the proposed method.