Results 321 to 330 of about 23,654,929 (387)
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Dynamic Cooperative Spectrum Sharing in a Multi-Beam LEO-GEO Co-Existing Satellite System
IEEE Transactions on Wireless Communications, 2021Among the existing satellite types, Low Earth Orbit (LEO) satellites provide short round-trip delays and are becoming increasingly important. Due to its low orbital profile, the LEO satellites can provide high-speed, low-latency and no dead zone network ...
Pengwenlong Gu +3 more
semanticscholar +1 more source
Acta Astronautica, 1978
Abstract In December 1974 and September 1975 two SYMPHONIE satellites were launched and successfully placed at 11.5° west longitude in the geostationary orbit. These satellites operate in the 4–6 GHz frequency band. Four transmission channels, each 90 GHz wide, are available for the experimental telecommunications mission. The spacecraft transponders
Burkhard R.K. Pfeiffer +1 more
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Abstract In December 1974 and September 1975 two SYMPHONIE satellites were launched and successfully placed at 11.5° west longitude in the geostationary orbit. These satellites operate in the 4–6 GHz frequency band. Four transmission channels, each 90 GHz wide, are available for the experimental telecommunications mission. The spacecraft transponders
Burkhard R.K. Pfeiffer +1 more
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Next‐generation global satellite system with mega‐constellations
International Journal of Satellite Communications And Networking, 2020Mega satellite constellations in low earth orbit (LEO) will provide complete global coverage; rapidly enhance overall capacity, even for unserved areas; and improve the quality of service (QoS) possible with lower signal propagation delays.
C. Ravishankar +4 more
semanticscholar +1 more source
Integrated satellite-HAP systems
IEEE Communications Magazine, 2005Thus far, high-altitude platform (HAP)-based systems have been mainly conceived as an alternative to satellites for complementing the terrestrial network. This article aims to show that HAP should no longer be seen as a competitor technology by investors of satellites, but as a key element for an efficient hybrid terrestrial-satellite communication ...
CIANCA, ERNESTINA +6 more
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IEEE Transactions on Aerospace and Electronic Systems, 2019
In this paper, a novel fractional-order fuzzy sliding mode control strategy is developed to realize the deployment of the tethered satellite system (TSS) with input saturation. The considered TSS is modeled as an underactuated system.
Shidong Xu +3 more
semanticscholar +1 more source
In this paper, a novel fractional-order fuzzy sliding mode control strategy is developed to realize the deployment of the tethered satellite system (TSS) with input saturation. The considered TSS is modeled as an underactuated system.
Shidong Xu +3 more
semanticscholar +1 more source
Journal of Telemedicine and Telecare, 1999
Satellite communication is a technique which has been used in telemedicine, often for educational purposes. Almost all of the work has concerned the use of fixed satellite terminals. Mobile satellite services MSS provide two-way voice and data communication from hand-held terminals, where the final link to the subscriber is by satellite.
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Satellite communication is a technique which has been used in telemedicine, often for educational purposes. Almost all of the work has concerned the use of fixed satellite terminals. Mobile satellite services MSS provide two-way voice and data communication from hand-held terminals, where the final link to the subscriber is by satellite.
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Astrometry in the Uranian system of satellites
AIP Conference Proceedings, 2008The predicted occultation between the satellites Miranda(UV) and Oberon(UIV) was observed on July 30, 2007 using SpeX/IRTF system and CODAM‐Paris Observatory facility. Data analysis reveals that the predicted magnitude drop for this phenomenon was overestimated and we establish an upper limit of 0m.05 for the phenomenon, perhaps due to a non‐lambertian
Mirel Birlan +4 more
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2008
After having studied the Earth’s Moon in Chap. 8, we now look at the moons of the other planets of the solar system. A quick look at the two moons of Mars is followed by a detailed examination of the four Galilean satellites of Jupiter: Io, Europa, Ganymede and Callisto.
William J. F. Wilson, Eugene F. Milone
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After having studied the Earth’s Moon in Chap. 8, we now look at the moons of the other planets of the solar system. A quick look at the two moons of Mars is followed by a detailed examination of the four Galilean satellites of Jupiter: Io, Europa, Ganymede and Callisto.
William J. F. Wilson, Eugene F. Milone
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15th International Communicatons Satellite Systems Conference and Exhibit, 1994
PanAmSat was originally conceived of as a low-cost, high performance, means for providing satellite services between the U.S. and Latin America. The company quickly evolved to become a worldwide competitive alternative to Intelsat. The current system consists of a single satellite providing Cand Ku-band services for the United States, Latin America ...
Michael Neuman +2 more
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PanAmSat was originally conceived of as a low-cost, high performance, means for providing satellite services between the U.S. and Latin America. The company quickly evolved to become a worldwide competitive alternative to Intelsat. The current system consists of a single satellite providing Cand Ku-band services for the United States, Latin America ...
Michael Neuman +2 more
openaire +2 more sources
Bell System Technical Journal, 1963
This paper describes the Telstar system and discusses the over-all system design. System considerations, the orbit selection and frequency allocation considerations are covered. A general description of the Telstar satellite and Andover, Maine, ground station provides background for companion articles in this series.
I. Welber, E. F. O'Neill, D. F. Hoth
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This paper describes the Telstar system and discusses the over-all system design. System considerations, the orbit selection and frequency allocation considerations are covered. A general description of the Telstar satellite and Andover, Maine, ground station provides background for companion articles in this series.
I. Welber, E. F. O'Neill, D. F. Hoth
openaire +2 more sources