LQG controller with wind gust disturbance rejection property for cassegrain antenna

Nowadays in most deep space exploration missions S- and X-band are used, but in order to increase the data rate, Ka-band is also gradually considered, designed and used in practice. The increased frequency band requires the cassegrain antennas to have a more accurate pointing ability, so the current cassegrain antenna servo system must be updated to meet the new requirement. This paper demonstrates the principles of LQG control algorithm, designs LQG controller with wind gust disturbance rejection property by state estimation and optimal feedback control, then applies it to a typical 34-m cassegrain antenna servo system. The simulation results reveal that LQG controller has a good wind gust disturbance rejection property, suppresses the disturbance transfer function significantly, and improves the command transfer function at the same time.