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See also
Spacecraft bus subsystem
typical, 351–58
Local oscillator (LO), 137
Zenit, 358
Long March, 355–56
L-band, 27–30
Long-term agreement (LTA), 363
center-fed parabola, 248
Lossless compression, 158
Inmarsat satellite, 335
Lossy compression, 159
MSS cells, 242
Low-density parity check (LDPC), 161
Low Earth orbit.
See
LEO satellites
MSS terminals, 334
Index
439
Low-noise amplifiers (LNAs), 139–40,
Mobile satellite service (MSS), 14, 17,
62–64, 100–101
321
ATC, 64
Low-noise block converter (LNB), 137,
development, 62–63
140
domestic service, 63
dc power for, 332–33
evolution, 100
triple, 334
GPS association, 101
wideband output, 333
hand-held satellite phones, 336
links, 133
M
service evaluation matrix, 392
Maintenance
spacecraft, 213
electronics, 385
systems engineering, 393
facilities/mechanical equipment, 386
user terminals, 334–36
information systems/software, 385
Mobility enhancements, 422–23
telecommunications network, 385–86
Modems, 306
Management interfaces, 360–61
Modulation, 165–72
Mandrel, 239
APSK, 171
Medium Earth orbit.
See
MEO
BEM, 171–72
MEO satellites, 342
defined, 151
defined, 21
digital, 165–72
orbit, 22
FSK, 169
Mexico, 59–60
intersymbol interference (ISI), 167
Microwave bands.
See
Frequency bands
PSK, 169–70
Microwave frequencies, 11–12
pulse, 166
Microwave lens antenna, 242
Modulators, 306
Microwave link engineering, 109–49
Monomethyl hydrazine (MMH), 350
decibels (dBs), 109–11
Moore’s law, 12
link quality, 142–49
Multipath, 131–33
propagation on Earth-space link,
caused by ionospheric scintillation,
111–33
131
transmitters and receivers, 133–42
defined, 131
Microwave propagation, 112–13
influence, 132
Middle East, 58–59
mobile, generation of, 133
Millimeter wave bands, 35–36
Multiple access, 172–83
Minimum shift keying (MSK), 188–89
ALOHA, 177–78
Mission
CDMA, 179–81
GEO profile, 257–58
defined, 151
launch, 338–49
FDMA, 173–75
non-GEO requirements, 259–60
methods, 172–83
on-station operation requirements,
RF bandwidth utilization in, 181–83
258–59
TDMA, 175–77
sequence, 258
Multiple beam switching, 209–12
summary, 257–60
Multiple-carrier IMD, 186–88
Mobile satellite communications, 99–104
Multiple-channel per carrier (MCPC)
ATC, 103–4
operation, 321
MSS, 100–101
Multiplexers
contiguous, 227–28
S-DARS, 101–3
440
Index
Multiplexers (continued)
O
filter combining into, 226
Offset fed geometry, 301–2
input, 227
Offset-fed parabolic reflectors, 249–51
output, 227
arrangement, 244
spurious response, 226–27
CP, 251
Multiplexing, 151, 307
dimensional characteristics, 249
Multipoint-to-point networks, 71
with feed and feed support, 250
reflector surface, 251
N
Offset QPSK (OQPSK), 188
Nahuel, 59
Omnidirectional antennas, 285–86
Near-field region, 113
On-orbit insurance, 400
Network economics, 412–19
Open Systems Interconnection (OSI)
network layout, 415–17
model, 86
space/ground segment optimization,
Operations and maintenance (O&M),
418–19
410–11
total network evaluation, 417–18
Operations control center (OCC), 16
traffic requirements, 412–15
Operations management, 384
See also
Economics
Orbital dynamics, 384–85
Network management, 375
Orbits
integrated, 380
configurations, 20–22
station (NMS), 375
non-GEO, 2
telecommunications, 385–86
period, 21
user, for routing/intersatellite relay,
placement in, 15–16
381
popular, 22
Network operating center (NOC), 380
Orion, 49–50
Network operations, 375–82
Output multiplexer (OMUX), 199
payload configuration management,
defined, 141
381–82
filters, 205
standard GEO transponder services,
power transfer, 142
376–79
user monitor and control, 379–81
P
Networks
Packet processing, 307
laying out, 415–17
Packet-switched services, 77–78
terrestrial, 421–22
Packet switching, 74
total evaluation, 417–18
Palapa system, 54–55
Next generation, 425–26
PanAmSat, 48–49, 53
Noise, 142–44
Parabolic reflectors, 246–51
uplink, 147–48
center-fed, 246–49
white, 143
focus-fed, 245
window, 23
offset-fed, 249–51
Non-GEO satellites
shapes, 247
atmospheric drag, 4
surface, 247
constellation creation, 14
Payload configuration management,
orbits, 2–3
381–82
See also
Satellites
Performance improvement, 162
Nonline-of-sight (NLOS) wireless, 4
North-south stationkeeping, 348
Perigee kick, 342
Index
441
Phase shift keying (PSK), 143–44,
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