ABSTRACT
This chapter discusses the design requirements and possible implementations for an on-board processor. The remainder of this discussion will be concerned with the payload data processing requirements and, in particular, the payload data programming issues. The characteristics of a generic scanning sensor will be summarized here to illustrate the processing requirements when using classical scanning sensor techniques. For the mission data processor (MDP) functions, the processing is general purpose in nature and throughput requirements are expected to be sufficient to require the use of multiple cooperating processors. The use of multiple processors to meet the throughput requirements implies parallel execution of the MDP algorithms. The requirements lead to a tentative conclusion that a network of general-purpose processors is best suited to performing the MDP task. The on-board computational requirements for satellites both under design and proposed have grown well beyond the capabilities of existing space- qualified computers.
