Figure 12.15
Artist’s rendering of the Intelsat-11 satellite in geostationary orbit. Built by Orbital
Sciences Corporation for Intelsat, Intelsat-11 carries two communications payloads:
a C-band payload to provide Fixed Satellite Services (FSS) to the continental United
States, Mexico and South America; and a Ku-band payload which serves DirecTV’s
Latin America downlink coverage in Brazil, with spot coverage over portions of
Mexico, Venezuela, and Florida. The satellite was launched in 2007 and is located
at 317 degrees east longitude. (
Source:
Orbital Science Corp.)
12.8
Conclusions for the Next Generation
427
References
[1]
Jacoby, C., ‘‘Overview of Systems Engineering,’’ Jacoby Consulting, Long Beach, CA, 2008.
[2]
Elbert, B. R.,
The Satellite Communication Applications Handbook,
2nd ed., Norwood,
MA: Artech House, 2004.
[3]
Watts, T. W., and D. A. Freedman,
Satellite Communications—Instant Infrastructure,
Bear
Stearns Equity Research, November 5, 1996.
About the Author
Bruce R. Elbert
is a leading authority on satellites and telecommunications, having
35 years of working experience at his own consulting firm, Application Technology
Strategy, Inc., and at Hughes, COMSAT, and the U.S. Army Signal Corps. He
directed the design of several major satellite projects, including Palapa A, Indone-
sia’s original satellite system; the Galaxy follow-on system, the largest and most
successful C-band satellite TV system in the world; and the first GEO mobile
satellite network to serve handheld terminals. By considering the technical, business,
and operational aspects of satellite systems, Mr. Elbert has contributed to the
economic success of several companies in the marketplace. In addition to an interna-
tional industrial background, he is a prolific writer of books and articles, and has
been featured as a speaker at numerous international conferences and seminars.
Mr. Elbert is the editor of Artech House’s Space Technology and Applications
Series, and the Technology Management and Professional Development Series. At
UCLA, he teaches satellite communications, information networking, and high-
tech marketing to practicing engineers. Mr. Elbert holds BEE and MSEE degrees
from CCNY and the University of Maryland, respectively, and an M.B.A. from
Pepperdine University. He has two daughters, Sheri and Michelle, and resides with
his wife, Cathy, in Thousand Oaks, California.
429
Index
2/3 switch, 221–22
Antenna patterns, 251–55
defined, 116
far-field, 252
A
global coverage horn, 240
Absorption, 125–27
near-omnidirectional antennas, 286
Adaptive-differential PCM (ADPCM),
shaped beam, 254
158
Antenna pointing, 265–68
A/D conversion, 156–58
accuracy, 266
defined, 156
Earth stations, 302
end-to-end performance, 157
LEO, 265–66
inaccuracy, 156–57
performance, 265
Advanced Communications Technology
static beam error, 266
Satellite (ACTS), 36
Antennas, 237–56
Advanced Technology Satellite (ATS),
beamwidth, 116–17
55–56
Cassegrain optics, 301
Africa, 60
directional properties, 115–18
ALOHA, 87, 177–78
directivity, 115–16
defined, 177
direct radiating array, 255–56
performance, 178
Earth station, 300–302
protocol operation, 178
gain, 115–16, 267
throughput efficiency, 177
horn, 237–43
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