TABLE OF CONTENTS The spacecraft bus is the platform that supports the communications payload during all phases of the mission, from launch, through injection into orbit, and throughout its operating lifetime. That is as challenging a task as processing and relaying the communications signals themselves and demands a thorough understanding of both the internal workings of the vehicle as well as its interaction with the various environments that are encountered both inside and outside the atmosphere. Across that spectrum of orbits and applications, the basic principles of bus design are fairly consistent. It is now a matter of adjusting the bus requirements to fit the mission.
The steps necessary to provide a working communications satellite or constellation are generally termed the mission. Just as in the conventional military counterpart, each step requires careful planning and proper execution. System engineers and mission planners spend considerable time and effort to anticipate all possible situations and contingencies that the spacecraft will or might experience and to provide the hardware, software, and procedures necessary for a satisfactory outcome. A detailed discussion of the processes and technologies is beyond the scope of this book; however, many of the more important aspects are reviewed in this chapter. Some additional methodologies can be found in [1].
As an aid in understanding the functions of the bus, we use the standard get-to-orbit mission as a prime example. The bus design must deliver the payload to orbit and support it throughout the operating lifetime. The...
