Today, embedded real-time applications play an important role in modern life. Satellites are
also robust embedded real-time applications. A satellite project can cost over three-hundred
million dollars. As many satellite manufacturers validate their satellites before launching,
satellite simulators play the most valuable role in validation infrastructures. Specifically,
satellite flight software validation has become more important. In this paper, we focused on the
round robin (RR), rate monotonic (RM), and event driven (ED) real-time scheduling task
methods with respect to their CPU usage performance for satellite simulator infrastructures.
The tasks are evaluated and tested by real-time executive for multiprocessor systems (RTEMS).
Those scheduling tasks are used in polling mode in the simulation setup. In this study, we
compared three task scheduler methods for attitude orbit control system tasks and MIL-STD
1553 bus data distribution controller tasks in a spacecraft simulator environment. The results
were close and the values were not segregated, thus, we chose RR and ED, because RR was
easy to implement and ED allowed for full control of the tasks.