Previous research in satellite constellation designs has focused on Low Earth Orbit (LEO) communication systems that service a global market of uniform demand. This paper addresses the challenge of designing a hybrid satellite system constellation (e.g., LEO satellites with elliptical orbiting satellites) to meet the demands of the emerging satellite broadband market. The broadband market model...

The general relativistic gravitomagnetic clock effect consists in the fact that two massive test bodies orbiting a central spinning mass in its equatorial plane along two identical circular trajectories, but in opposite directions, take different times in describing a full revolution with respect to an asymptotically inertial observer. In the field of the Earth such time shift amounts to 10−7 s...

[1] Microwave humidity measurements from polar orbiting satellites are affected by diurnal sampling biases which are caused by changes in the local observation time of the satellites. The long-term data records available from these satellites thus have spurious trends, which must be corrected. Diurnal cycles of the microwave measurements have been constructed by combining data over the period 2...

We study the evolution of dark matter satellites orbiting inside more massive haloes using semi-analytical tools coupled with high-resolution N-Body simulations. We select initial satellite sizes, masses, orbital energies, and eccentricities as predicted by hierarchical models of structure formation. Both the satellite (of initial mass Ms,0) and the main halo (of mass Mh) are described by a Nav...

Introduction Space systems are characterized by the huge cost induced by their design, their launch, and their maintenance. Furthermore, these systems have to satisfy more and more difficult criteria of performance or quality of service. Thus, the management of resources involved in these systems leads to specific and complex optimization problems [Hall 94, Frank 01]. There are two main kinds o...

Communication via satellite begins when the satellite is positioned in the desired orbital position. Ground stations can communicate with LEO (Low Earth Orbiting) satellites only when the satellite is in their visibility region. The duration of the visibility and so the communication duration varies for each satellite pass at the ground station, specifically for LEO satellites which do move too...