Star To The Optical Communication System Atp Software Control Module Developed

Space optical communication application has now become a hot research field of communications. Space optical communication has high security, high rate, high bandwidth, interference and light weight, small size and low power consumption. Space optical communication has many technical challenges, which, alignment, acquisition and tracking (Acquisition, Tracking, Pointing, - ATP) technology is one of the most important technology. The acquisition / tracking performance will directly determine the optical communication link established between satellite and ground or not. Therefore, high performance, high precision ATP system for satellite to ground optical communication is the focus of the study.This optical communication the tracking control loop ATP subsystem research, from the ATP system operation and control of most of the software, start the preparation, analysis and design, in this based on the use of FPGA-based chip, using Altera's soft-core CPU NIOSII to achieve the tracking and alignment capabilities.In this issue I in charged with the design of tracking control module of ATP and implementation. First, the FPGA-based platform for tracking module and the external circuit hardware were designed. For two different tracking courses of coarse tracking and fine tracking, the design in the FPGA chip to implement the different functional units of the tracking control system, including coarse tracking CCD interface design, coarse tracking CCD interface design, encoder interface design, FPGA interface design and D/A conversion unit design. Secondly, in the FPGA chip designed the embedded soft processor NIOSII, and in the soft-core platform process the spot image on the CCD including spatial filtering techniques, centroid calculation; used Digital PID algorithm to control movement of DC motors and FSM respectively; control of the workflow of ATP subsystem. Finally, participate in system testing, and analyze the performance of build soft-core.In the ATP system, involves real-time processing of high frame rate CCD controlled function. The use of a common microcontroller, external circuit complex and can not meet the accuracy index, tracking error and the filtering algorithm requirements. The use of soft-core CPU processors NIOSII can meet the computing needs of the premise on, reducing the system size. NIOSII is to use the degree of increase and of the way to improve performance, not simply by increasing the system operating frequency, so relative to other CPU, its power consumption.