Small Satellites Constellations & Network: Architectures and Technologies

Based on two constellation missions cases ( data collect and disaster monitoring by SAR radar ), the study derives architectural and related technologies required in the field of future commercial « small » onstellations. Global management from centralized control station is chosen here, with intermitent inter-plan visibility for 1SL, as imposed by the low altitude and moderatly populated parameters

Role of the excited electronic states in the ionization of ambient air by a nanosecond discharge

International audienceIn this paper, the mechanism of air ionization by a single nanosecond discharge under atmospheric conditions is studied by numerical simulations. The plasma kinetics is solved with ZDPlasKin and the electron energy distribution function is calculated with BOLSIG+. The originality of the model is to consider not only the excited electronic states of N2, but also the excited electronic states of O and N. These states are shown to have a primary importance in the ionization of the plasma for ne > 10 17 cm-3. It is shown that a non-equilibrium plasma (Te > Tgas) at ne = 10 17 cm-3 can reach full ionization and thermalization (Te = Tgas ≈ 3 eV, ne ≈ 10 19 cm-3) in less than half a nanosecond under a field usually encountered in nanosecond discharges