Exploring Physical Frame Format Design and Synchronization Algorithm for Optical Communication

Space optical communication has been a hot topic in modern communication system research, because it has many advantages, such as good secrecy, large information capacity, strong anti-interference ability, and so on. Pulse position modulation (PPM) is an excellent modulation method. In view of the low rate of information transmission by a space optical communication system, an improved "empty-empty-zero" physical frame format is designed to improve its transmission rate. In view of the actual space laser digital receiver, the frame synchronization algorithm is designed in this paper. Based on the physical frame format, this paper focuses on the design of frame synchronization algorithm. In order to deal with the change of noise and other parameters, an adaptive threshold setting is proposed. Considering the engineering implementation, a simplified correlation filtering implementation method is proposed. Finally, we designed the reception prototype system based on FPGA. The Matlab simulation, online simulation and experimental verification prove that the proposed method is correct and reliable