Propagation considerations for emerging satellite communications applications
Article Abstract:
The effects of rain and other propagation concerns for new satellite communications applications are examined. Among these areas are very small aperture terminal (VSAT) systems using low operating margins and/or low elevation angles, traditional communications applications operating with inclined geosynchronous orbits, and mobile and personal communications applications using networks of low earth orbit (LEO) satellites. All of these applications rely on small communications terminals with inherent small link margins; the performance of these terminals will be affected by atmospheric propagation impairments much more than larger, higher-margin systems. Rain attenuation will remain a problem, but cloud attenuation, scintillation, and gaseous attenuation will also be greater potential impairments. The operational parameters of low-margin, low-elevation-angle, inclined geosynchronous, and LEO systems are studied.
Publication Name: Proceedings of the IEEE
Subject: Electronics
ISSN: 0018-9219
Year: 1993
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Ray-mode analysis of complex resonances of an open cavity
Article Abstract:
A generalized wavefront-resonance, partial-resonance method undergoes a modal expansion to enable the association of partial, internal high-Q frequencies with waveguide modes to enable the parameterization of the global scattering behavior of objects whose shape is an arbitrary-length enclosure with one open end and parallel, thin walls. A hybrid form of ray-mode coupling is used to construct a global resonance equation, the solution of which generates the resonant frequencies for the complex, composite object. Global resonances are affected by different components of the object, so the frequencies can be analyzed to obtain structural information about the object. Development, underlying equations, and application of the ray-mode analysis technique are described.
Publication Name: Proceedings of the IEEE
Subject: Electronics
ISSN: 0018-9219
Year: 1989
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- Abstracts: The quasiparticle view of wave propagation. Propagation considerations in satellite communication systems
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