Linear quadratic integrated versus separated autopilot-guidance design

Two types of guidance and control design concepts are explored: a traditional separated approach and an integrated one. Using the integrated approach, two different guidance systems are presented: a single-loop guidance law and a two-loop autopilot-guidance law. In the two-loop case, the autopilot loop is designed separately from the guidance one, but all the states are fed back into the guidance loop. It is proven that the integrated guidance laws achieve the same performance for single-input single-output systems. The performance of the three guidance laws is evaluated and compared via a thrust vector control missile. It is shown that the performance of the separated guidance law is inferior to that of the integrated laws.