Results 151 to 160 of about 968,206 (211)
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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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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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Satellite power system simulation
Acta Astronautica, 1997Abstract In order to furnish a useful tool for the power system preliminary sizing, a satellite power system simulator was developed. The simulator has a modular structure where each module implements the mathematical model of the system components (solar array, battery, voltage regulators etc.).
COLOMBO G +4 more
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Satellite Communications Systems
2020ÖZET UYDU HABERLEŞME SİSTEMLERİ Modern askeri operasyonlarda uzay çok önemli bir unsurdur. Bilgi toplama, işleme ve dağıtımı konusunda uydu sistemleri eşsiz kabiliyetleri nedeniyle gelişen geleceğin muharebe sahasında bu sistemlerin önemli bir rolü vardır. 21.
Gérard Maral +2 more
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Satellite-Based Navigation Systems
2012This chapter focuses on various satellite-based navigation systems. The most well-known and widespread system currently used for localization of a radio-receiving terminal is the global positioning system (GPS). All GPS satellites share the same frequency bands, making use of the code division multiple access (CDMA) technique. The transmitted signal on
Bacci G. +5 more
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Proceedings of the IEEE, 1978
This paper describes the measurement techniques employed to test the elements of a communications satellite system. Techniques for measuring the gain-to-noise-temperature ratio (G/T) of an earth station antenna are presented. The measurement of earth station polarization characteristics is discussed extensively in terms of the new requirement for ...
R.W. Kreutel, D.F. DiFonzo, C.E. Mahle
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This paper describes the measurement techniques employed to test the elements of a communications satellite system. Techniques for measuring the gain-to-noise-temperature ratio (G/T) of an earth station antenna are presented. The measurement of earth station polarization characteristics is discussed extensively in terms of the new requirement for ...
R.W. Kreutel, D.F. DiFonzo, C.E. Mahle
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IETE Journal of Education, 1995
Tracking of a satellite provides the most vital information about its position and its orbit in space. Tracking is very much essential not only during its launch for initial critical maneuvers but even after launch to maintain it in assigned slot in space.
S N Prasad, S Pal, S G Basu
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Tracking of a satellite provides the most vital information about its position and its orbit in space. Tracking is very much essential not only during its launch for initial critical maneuvers but even after launch to maintain it in assigned slot in space.
S N Prasad, S Pal, S G Basu
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Satellite Communication Systems
2004Satellite-based communication has become a major facet of the telecommunication industry for two major reasons. First, it provides a means of broadcasting information to a large number of people simultaneously. Thus, satellite communication systems are an important ingredient in the implementation of a global communication infrastructure.
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MILCOM 2007 - IEEE Military Communications Conference, 2007
In today's unpredictable and dynamic environment, flexibility is an important aspect in system design. Flexibility increases system capability and effectiveness, reduces long term cost, encourages innovation, and protects against uncertainty. It is often at odds with optimization.
Philip J. Lin, Thomas J. Kostas
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In today's unpredictable and dynamic environment, flexibility is an important aspect in system design. Flexibility increases system capability and effectiveness, reduces long term cost, encourages innovation, and protects against uncertainty. It is often at odds with optimization.
Philip J. Lin, Thomas J. Kostas
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2015
In this chapter, we review principles of hybrid radio access systems that are able to provide both terrestrial and satellite connectivity. Practical examples of the existing hybrid systems, such as digital video broadcasting-satellite services to handheld devices and TerreStar system, are also reviewed.
Juha Ylitalo +6 more
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In this chapter, we review principles of hybrid radio access systems that are able to provide both terrestrial and satellite connectivity. Practical examples of the existing hybrid systems, such as digital video broadcasting-satellite services to handheld devices and TerreStar system, are also reviewed.
Juha Ylitalo +6 more
openaire +3 more sources