Power-Efficient Software Architecture for a CubeSat System

A 2U CubeSat, (20cm by 10 cm by 10 cm) is being developed to make impedance measurements of plasma in the ionosphere at 400 km altitude. Because the new instrument is able to make measurements rapidly, and because of the severe power and size constraints of the satellite, special care is needed in storing the measurement data and transmitting it to Earth. For both the measurements and for general housekeeping functions, the software of the CubeSat must be able to respond rapidly to events and operate in a manner that is not only flexible and extensible but also power efficient. This work outlines the process by which the software was designed to satisfy the constraints of the mission.