Parametric comprehensive optimization design of high accuracy tracking control system for satellite optical communication

Accurate tracking and alignment control systems play a vital role in satellite optical communications. China's completed Mozi quantum science experimental satellite uses a tracking and aiming system based on the classical follow-up system theory design, and achieved a satisfactory effect in practice. Space quantum communication application for farther distance in the future puts forward higher precision requirements for the aiming and tracking system, which is difficult to meet when using the traditional control method. To this end, this paper proposes a parametric design method for the aiming system, abandoning the idea of separate design of fine and coarse systems of the traditional methods, and designing the two-stage subsystems as a whole, making full use of the design freedom in the system. By comprehensively optimizing the design degrees of freedom, the system meets various design requirements such as decoupling step disturbance and attenuating complex interference, insensitive pole assignment and minimizing control gain, which significantly improves the alignment accuracy. The simulation results show that the alignment accuracy is improved from the original micro-arc metric to the nano-arc metric. © 2020, Editorial Department of Control Theory & Applications South China University of Technology. All right reserved.