Cost Variance Analysis in Constellation Architecture Studies

A satellite constellation is group of satellites, which may be identical or varying, but designed together to jointly operate. The architecture of a satellite constellation includes decisions on individual satellite capabilities, payload approaches, placements in orbits, and replenishment strategies. In all architecture studies, cost (including development, production, and launch) is a central concern, including the variance or uncertainty of cost. A common complexity in constellation studies is due to multiple different but nonindependent satellite designs. This article discusses methods for estimating cost variances using probabilistic models at the satellite configuration level extended to constellations of satellites and including correlations due to shared design content. This article uses the NOAA Satellite Observing System Architecture study as a worked example. An important application of estimates of partially correlated costs is assessing the significance of cost estimate differences among alternatives.