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2019
As a part of the European Space Agency mission "EXPOSE-R2" on the International Space Station (ISS), the BIOMEX (Biology and Mars Experiment) experiment investigates the habitability of Mars and the limits of life. In preparation for the mission, experimental verification tests and scientific verification tests simulating different combinations of ...
Huwe, Björn +5 more
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As a part of the European Space Agency mission "EXPOSE-R2" on the International Space Station (ISS), the BIOMEX (Biology and Mars Experiment) experiment investigates the habitability of Mars and the limits of life. In preparation for the mission, experimental verification tests and scientific verification tests simulating different combinations of ...
Huwe, Björn +5 more
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Beyond low earth orbit. An overview of orbit-to-orbit stages
Acta Astronautica, 1986New developments in upper stages are discussed. Tables revealing the dimensions, engine types, total thrust, weight, payload, and sponsor for developed and planned upper stages compatible with Space Transportation System (STS) or expendable launch vehicles are presented.
Joseph P. Loftus, Warren L. Brasher
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Enhancing GNSS by integrating low Earth orbiters
2022In dieser Arbeit wird eine Verbesserung der globalen Satellitennavigationssysteme (GNSS) durch die Einbindung von Satelliten in niedrigen Erdumlaufbahnen (LEOs) in eine gemeinsame präzise Bahnbestimmung (POD) vorgestellt. Das von den Vereinigten Staaten betriebene Global Positioning System (GPS) wird stellvertretend für alle GNSS untersucht.
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Performance of Low Earth Orbit Satellite Systems with Coding
Wireless Personal Communications, 2002The effect of block, convolutional and Turbo coding on the probability of error and the capacity are investigated for CDMA Low Earth Orbit (LEO) Satellite systems. The model employed assumes a contaminated Gaussian traffic model to be more compatible with different population areas.
Hebatallah M. Mourad +3 more
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Yaliny's protocol for low earth orbit satellites
2015 IEEE East-West Design & Test Symposium (EWDTS), 2015This paper presents a modification of CCSDS 131.2-R-2/DVB-S2 standard developed by Yaliny Engineering. The modification has special features — Doppler offset compensation with prior information, low latency synchronization scheme, which allows for its use on LEO satellites and patent-free LDPC codec.
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Precise Autonomous Orbit Control in Low Earth Orbit
AIAA/AAS Astrodynamics Specialist Conference, 2012This paper analyses the problem of the autonomous absolute orbit control of a space- craft in low Earth orbit using different on-board feedback control systems. Three types of control are compared. The first implements an analytical control algorithm. The second and third controllers considered are the linear and the quadratic optimum regulator from
De Florio, S., D'Amico, S., Radice, G.
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AERODYNAMICS IN LOW EARTH ORBIT
The orbital evolution of CubeSats operating in low Earth orbit is strongly influenced by atmospheric drag, particularly during periods of elevated solar activity, which follows an approximately 11-year solar cycle, Enhanced extreme ultraviolet radiation during solar maximum leads to significant heating and expansion of the thermosphere, increasing ...openaire +1 more source
Kinematic Orbit Determination for Low Earth Orbiters (LEOs)
2002Kinematic point positioning of a Low Earth Orbiter (LEO) using GPS data is one possibility to get precise orbit information. This approach is followed at the Astronomical Institute of the University of Bern (AIUB) as an alternative to the dynamical orbit determination.
H. Bock, G. Beutler, U. Hugentobler
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Orbital debris environment in low Earth orbit: An update
Advances in Space Research, 1993Abstract Until recently, the definition of the orbital debris environment depended upon mathematical models and limited data which had been obtained as a side product of other space related operations. Measurements conducted to specifically determine the orbital debris environment are now being conducted. These measurements are confirming the general
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