Development of an algorithm for real time control of a satellite tracking system

A numerical algorithm is developed for optimized satellite tracking antenna position alignment. An optimal control law is presented for a linear plant with separated nonlinearity. A solution is found for a linear optimal tracking problem, assuming the station has a saturation nonlinarity. The nonlinearity function is inverted and constrained to values imposed by the saturation limit, thereby generating the control values. Estimates of reference angles are made at the ends of sampling periods, while state estimates are made at the beginning. The state is propagated through the intervals with a state transition matrix. Calculations of the control signals take place only during optimized time intervals, i.e., multiples of the sampling intervals. The efficacy of the method is illustrated by a simulation of tracking of a LEO spacecraft.