1. Description of the need for a satellite system

The genesis of any satellite system lies in the precise identification of a need. This process generally begins with the detailed formulation of this need by a satellite operator, whether it be a commercial, government, or research entity.

The expression of need is positioned in the first phase of the ECSS (European Cooperation for Space Standardization) model phases. The phases follow the ECSS model or equivalent:

• Phase A: expression of requirements, feasibility (conceptual studies, trade-offs);

• Phase B: specification, preliminary design (detailed definition of requirements);

• Phase C: Detailed design (modeling, design validation);

• Phase D: development, manufacturing, testing, assembly, integration, and launch (including...