Results 111 to 120 of about 6,131 (159)

Collision matrix for low earth orbit satellites

Journal of Spacecraft and Rockets, 1989
The low Earth orbit (LEO) is becoming cluttered with thousands of satellites, rocket bodies, and a variety of space garbage. This collection of objects crossing paths at speeds on the order of 10 km/s is creating an increasing collision hazard to many operational systems. The effect that the destruction of LEO satellites will have on other users of the
Darren McKnight, Gary Lorenzen
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Low earth orbit satellite systems for communications

International Journal of Satellite Communications, 1991
AbstractIt may be that we are now entering the era of LEO constellation satellite communications after thirty years of domination by the GEO systems. This paper heralds the coming of the new era with a tutorial approach to the system design and trade‐offs of LEO constellation system design.
Gérard Maral, Jean‐Jacques de Ridder, Barry G. Evans, Madhavendra Richharia   +3 more
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Low Earth orbit satellite technology for PCS

MILCOM 92 Conference Record, 2003
The authors examine today's major issues in terrestrial personal communication systems (PCS) and show the emerging technologies necessary for global PCS. It is suggested that, with the development of existing technologies and the spectrum allocations, the Iridium system of low Earth orbit satellites will revolutionize PCS to make telecommunications a ...
P.N. Cloutier, P.A. Swan
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GEO data relay for low earth orbit satellites

2012 6th Advanced Satellite Multimedia Systems Conference (ASMS) and 12th Signal Processing for Space Communications Workshop (SPSC), 2012
This paper focuses on a novel, conceptual data relay system for relaying data transfer between low earth orbit (LEO) satellites and a gateway through a geostationary earth orbit (GEO) satellite, developed in the framework of the GeReLEO project. Novel channel adaptive transmission schemes are introduced in addition to the access scheme supporting ...
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Exploring Positioning Through Pseudoranges Using Low Earth Orbit Satellites

2022
Abstract: For decades, Global Navigation Satellite Systems (GNSS) have been dominant in the Positioning, Navigation and Timing (PNT) market. Improvements have been made to the design and implementation throughout the years. Recently, however, growing demand has emerged for alternative PNT solutions.
Van Uytsel, Wout, Janssen, Thomas, Halili, Rreze, Weyn, Maarten   +3 more
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Magnetic Attitude Control System for Low-Earth Orbit Satellites

Multibody System Dynamics, 2001
The stabilization of a small spacecraft on the low-Earth orbit is done by a three-axis magnetometer. Both orbital motion parameters and attitude can be estimated by the vector function Lyapunov method. The authors also propose a recursive state estimation algorithm with enhanced convergence.
Lebedev, D., Tkachenko, A.
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Yaliny's protocol for low earth orbit satellites

2015 IEEE East-West Design & Test Symposium (EWDTS), 2015
This 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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Performance study of low Earth-orbit satellite systems

IEEE Transactions on Communications, 1994
The performance of low-earth-orbit satellite systems is investigated in terms of the average number of beam-to-beam handoffs, the average number of satellite-to-satellite handoffs, the channel occupancy distribution, and the average call drop probability.
Ganz, A, GONG, YB, LI, B
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