picture of the encyclopedia
previous next
Focus
Version 0.81 comes with a new web design! Please allow popups for navigation.

Glossary



ADC Analog to Digital Conversion
Apogee The orbital point were the satellite is furthest from the earth
Apogee Kick Motor (AKM) A motor on board the satellite that enables the satellite to move from GTO to GEO
Bandwidth Range on frequency the transponder can transmit, in MHz Give a measure of capacity
BOL Begin Of Life
BUD Big Ugly Dish
Carrier to Noise ratio (C/N) Ratio which express the quality of a signal (the higher the better)
Catalog number The number that identifies a satellite, attributed by NASA. See CATNR
CDMA Code Division Multiple Access. Access method for several stations to go through a single transponder which uses spread spectrum modulations and orthogonal codes.
Clarke belt The geostationary orbit, named after Arthur Clarke who first said that such an orbit should exist in 1945. He died at the age of 90 in March 2008.
COMINT Communication Intelligence
CONUS Continental United States (all states but Alaska and Hawaii)
Coverage Zone where the satellite's signals can be received
DBS Direct Broadcast Satellite
dBW ratio of the power to one Watt in decibels (unit used to express EIRP values)
DC power Total power produced by the solar panels or nuclear reactor
DCME Digital Circuit Multiplication Equipment
DCP Data Collection Platform
Downlink The satellite to earth signal path
DTH Direct To Home
EIRP Effective Isotropic Radiated Power
Technical value that evaluates the strength of receive signals
ELINT Electronic Intelligence
EOL End Of Life
FDMA Frequency Division Multiple Access Access method to a transponder by multiple stations each using 1 unique frequency
Footprint A map of EIRP values that express the signal strengths at a given location
Frequencies (GHz if not specified)
HF-band 1.8 - 30 MHz
VHF-band 50 - 146 MHz
P-band 0.230 - 1.000
UHF-band 0.430 - 1.300
L-band 1.530 - 2.700
FCC's digital radio 2.310 - 2.360
SHF-band 3 - 30
S-band 2.700 - 3.500
C-band Downlink: 3.700 - 4.200
Uplink: 5.925 - 6.425
Standard US chart (horizontal)
Standard US chart (vertical)
X-band Downlink: 7.250 - 7.745
Uplink: 7.900 - 8.395
Ku-band (Europe) Downlink:
FSS: 10.700 - 11.700
BSS/DBS: 11.700 - 12.500
Telecom: 12.500 - 12.750
Uplink:
FSS & Telecom: 14.000 - 14.800
BSS/DBS: 17.300 - 18.100
Ku-band (America) Downlink:
FSS: 11.700 - 12.200
BSS/DBS: 12.200 - 12.700
Uplink:
FSS: 14.000 - 14.500
BSS/DBS: 17.300 - 17.800
Ka-band Uplink: 28.4-28.6 GHz & 29.3-30.0 GHz
Downlink: 18.3-18.5, 18.6-18.8 GHz & 19.7-20.2 GHz
EHF-band 30 - 300
V-band 36 - 51.4

http://www.ntia.doc.gov/osmhome/nebbia.html
GEO Geostationary Earth Orbit
Geostationary orbit The circular orbit at 35.780 km above the equator. Satellites slotted on this orbit always appear at the same position in the sky. In degrees towards East (E or positive) or West (W or negative) from the Greenwich meridian.
G/T Unit of measurement for an antenna + LNA Expressed from the gain and and noise temperature. The higher the better
GTO Geostationary Transfer Orbit
Geostationary satellites are usually launched on a temporary orbit before being moved to GEO
Inclined Orbit Term used for a GEO satellite that has turned off its North/South stabilization. From Earth, such a satellite seems to draw an 8 in the sky; part of the day it is above the Equator, and then below.
IOL Inter-Orbit Link
Launch id Launch number that identifies the flight, see LAUNR
LEO Low Earth Orbit
LNA Low Noise Amplifier
LHCP Left Hand Circular Polarization
LTWTA Linearized Traveling Wave Tube Amplifier
Microsat Satellite weighing between 10 and 100 kg
Minisat Satellite weighing between 100 and 1000 kg
Nanosat Satellite weighing between 1 and 10 kg
PAM Payload Assist Module
Perigee The orbital point were the satellite is closest from the earth
Picosat Satellite weighing less than 1 kg
Polar orbit Orbit that is perpendicular to the plan of the Equator
Polarization Plane of vibration of the electrical field of a signal Differerent polarizations enable better frequency re-use
Power The transponder amplification power
RADINT Radar Intelligence
RHCP Right Hand Circular Polarization
SCPC Single Channel Per Carrier
Access method for a large number of signals to go through a single transponder
SIGINT Signal Intelligence
SSPA Solid State Power Amplifier
TDMA Time Division Multiple Access Access system where each station has a time slot for using a unique carrier shared with others
THEO Twelve Hours Excentric Orbit ( Molniya-type orbit)
Transponder The association of a receiver, frequency converter and transmiter devices in a satellite
TWTA Traveling Wave Tube Amplifier
Uplink The earth to satellite signal path

© TBS Internet, all rights reserved. All reproduction, copy or mirroring prohibited. Legal notice
francais anglais contact