In the presence of high-frequency unmodeled dynamic uncertainty and low-frequency wind disturbance,the conventional PID control algorithm cannot provide high pointing and tracking accuracy for large-diameter antennaservo system.In order to solve this problem,a mixed-sensitivity H_infinity control algorithm based on the sensitivityfunction and the complementary sensitivity function,which possesses high system performance and strongstability,is designed and applied to the antenna servo system.Simulated results indicate that the proposed algorithmnot only significantly improves the dynamic performance of the antenna servo system but also possesses strongdisturbance rejection ability and robustness.