Publications associées à Télévision par satellite

A possible dwarf galaxy satellite-of-satellite problem in ?CDM

Dark matter clusters on all scales, and it is therefore expected that even substructure should host its own substructure. Using the Extragalactic Distance Database, we searched for dwarf-galaxy satellites of dwarf galaxies, that is, satellite-of-satellite ...

EDP SCIENCES S A2023

The cis-lunar ecosystem — A systems model and scenarios of the resource industry and its impact

Jean-Paul Richard Kneib

Lunar resources is one of the many new putative business models that may transform space logistics. Yet it competes with Earth-based resources, in a complex trade-off involving both tech development & socioeconomic dynamics. This study models the size vs. ...

2021

QUIC: Opportunities and threats in SATCOM

Ludovic Bernard Gérard Thomas, Emmanuel Qays Dubois

This article proposes a discussion on the strengths, weaknesses, opportunities and threats related to the deployment of QUIC end-to-end from a satellite-operator point-of-view. The deployment of QUIC is an opportunity for improving the quality of experienc ...

IEEE2020

Small satellites for space science A COSPAR scientific roadmap

Volker Gass, Jie Wu, Maurice Borgeaud

This is a COSPAR roadmap to advance the frontiers of science through innovation and international collaboration using small satellites. The world of small satellites is evolving quickly and an opportunity exists to leverage these developments to make scien ...

ELSEVIER SCI LTD2019

Calibration Aspects of INS Navigation

Philipp Clausen

The use of a Bayesian filter (e.g., Kalman filter) for the fusion of information from satellite positioning and inertial navigation is a common approach in many applications, where the knowledge of position, velocity, and attitude in space are of great int ...

EPFL2019

Comparison of L1 and L5 Bands GNSS Signals Acquisition

Cyril Botteron, Jérôme Leclère

Nowadays, civil Global Navigation Satellite System (GNSS) signals are available in both L1 and L5 bands. A receiver does not need to acquire independently the signals in both bands coming from a same satellite, since their carrier Doppler and code delay ar ...

2018

Hypervelocity impact testing on stochastic and structured open porosity cast Al-Si cellular structures for space applications

Andreas Mortensen

A hypervelocity (6.7–7.0 km/s) impact testing campaign was conducted using Ø 2 mm, 95% Al projectiles onto A357 aluminium alloy stochastic foams with 4–5 mm typical pore dimensions, or alternatively diamond cubic periodic structures of cast AlSi12 with a 6 ...

2018

Guidance, Navigation and Control for Autonomous Rendezvous and Docking of Nano-Satellites

Camille Sébastien Pirat

Is it possible to dock CubeSats in Low Earth Orbit? Challenges are associated with the level of miniaturisation: the docking accuracy is driven by the docking mechanism dimensions. The achievable docking performance with the Guidance, Navigation and Contro ...

EPFL2018

3D-printed Ka-band Antenna Based on Stereolithography

Juan Ramon Mosig, Tomislav Debogovic, Maria Garcia Vigueras, Joana Rita Alves dos Santos Silva

This paper presents a circularly-polarized dual-band antenna for Ka-band satellite communications which operates simultaneously in both civil and military downlink (17.7-21.2 GHz) and uplink (27.5-31 GHz) bands. The antenna is composed of a metallic ridged ...

IEEE2017

Study on the cross-correlation of GNSS signals and typical approximations

Pierre-André Farine, Cyril Botteron, Jérôme Leclère

In global navigation satellite system (GNSS) receivers, the first signal processing stage is the acquisition, which consists in detecting the received GNSS signals and determining the associated code delay and Doppler frequency by means of correlations wit ...

Springer Verlag2017