Item
s Definitions Terms
1
Also called as Multiple Destination, It implies that more than one user has access to one or more radio
channels within a satellite communications channel.
Multiple Accessing Arrangement:
Frequency-division multiple accessing (FDMA)
Time-division multiple accessing (TDMA)
Code-division multiple accessing (CDMA) Multiple
Accessing
2
A given number of the available voice-band channels from each earth station are assigned a dedicated destination.
Pre-assignment (dedicated) 3 Voice channels are assigned on an as-needed basis.
Demand Assignment
4
The method of assigning adjacent channels different electromagnetic polarizations and is possible by using orthogonal polarization and spacing adjacent channels
20 MHz apart. Frequency Reuse
5 Eskimo word meaning “little brother”. Anik
6 Domestic Satellites operated by Telsat Canada.
Anik-E
communications Satellite
7
A method of multiple accessing where a given RF
bandwidth is divided into smaller frequency bands. FDMA
8
Multiple channels per carrier formats assigned and remain fixed for a long Period of time.
Fixed-Assignment, Multiple
Access (FAMA)
9 Assigning carrier frequency on temporary basis using a statistical assignment process.
Demand-Assignment Multiple Access 10
An acronym for Single-channel-per-carrier PCM
multiple Access Demand-assignment Equipment. SPADE 11 Stands for Single-Carrier-Per-Channel. SCPC 12 A time division-multiplexed transmission that is
frequency division multiplexed. Common
Signaling Channel
(CSC)
13
The predominant Multiple-access method of time division multiplexing digitally modulated carriers between participating earth stations within a satellite
network through a common satellite transponder. TDMA
14
An RF-to-RF repeater that simply receives the earth station transmissions, amplifies them, and then
retransmits them in a downlink beam that is received by
all other participating station. Transponder
15
It is where transmissions from all earth stations are
synchronized. Reference Burst
16 It is where all receiving stations recover a frequency and phase coherent carrier for PSK demodulation.
Carrier Recovery Sequence
(CRS)
17
An acronym for, Conference of European Postal and Telecommunications Administrations, is commonly used
TDMA frame format for digital satellite system. CEPT
18
Sometimes referred to as Spread-Spectrum Multiple entire allocated bandwidth Access, the transmissions can spread throughout.
Code-Division Multiple Access CDMA)
19 A unique binary word that each earth station’s
transmissions are encoded. Chip Code
20 It compares two signals and recover the original data. Correlator
21
It assigns an individual terrestrial channel (TC) to a particular satellite channel (SC) for the duration of the call.
Digital non interpolated Interface
22
It assigns a terrestrial channel to a satellite channel only when speech energy is present on the TC.
Digital Speech Interpolated Interface
23
A form of analog channel compression that has been used for sub oceanic cables for many years.
Time-Assignment Speech
Interpolation (TASI)
24
The art or science of plotting, ascertaining or directing the course of movements, in other words, knowing
where you are and being able to find your way around. Navigation
25
It is the most ancient and rudimentary method of navigation and simply continuing to travel about until you reach your destination, assuming of course that you
have one. Wandering
26
Earliest effective means of navigation wherein direction and distance are determined from precisely timed sightings of celestial bodies, including the stars and
moon. Celestial
Navigation 27 Method of navigation by means of fixing a position and Piloting
direction with respect to familiar, significant landmarks such as railroad tracks, water towers, barns, mountains and bodies of water.
28 A navigation technique that determines position by
extrapolating a series of measured velocity increments. Dead Reckoning
29
The term derived from the word “deduced” and not necessarily from the fate of the people who used the
technique. Dead
30
He used dead reckoning successfully in 1927 during his
historic 33-hour transatlantic journey. Charles Lindbergh 31
She attempted to make the first around-the-world in
1937 using the dead reckoning technique. Amelia Earhart
32
Navigation technique wherein the position is determined by measuring the travel time of an electromagnetic
wave as it moves from a transmitter to a receiver. Radio Navigation 33 A radio Navigation system for terrestrial surface
broadcast. Decca
34 Radio Navigation system that provides global coverage
and terrestrial surface broadcast. Omega
35 Also a terrestrial surface broadcast. LORAN
36 Low-orbit satellite broadcast that provides global
coverage. Navy Transit GPS
37 Medium-orbit satellite broadcast also provides global
coverage. Navstar GPS
38
Means of radio navigation in which receivers acquire Coded signals from two pairs of high-powered, land based transmitters whose locations are precisely
known. LORAN
39 An acronym for Navigation System with Time and
Ranging. Navstar
40
An abbreviation for Global Positioning System.
Two levels of service or accuracy:
Standard Positioning Service
Precise Positioning Service GPS
41
A satellite-based open navigation system which simply means that it is available to anyone equipped with a GPS receiver.
Consists of three segments:
a space segment
a ground control segment
user segment Navstar GPS
42
It was when the Navstar declared as fully operational by
the U.S. Air Force Space Command. April 27, 1995 43
It was completed in 1994 and is maintained by the United States Air Force.
Navstar Satellite System
44
A positioning and timing service that is available to all GPS users on a continuous, worldwide basis with no direct change.
Standard Positioning Service
45
Sometimes called Space Segment, consists of 24operational satellites revolving around Earth in six orbital planes approximately 60° apart with four
satellites in each plane. Satellite Segment
46 It produces highly accurate timing signals for satellites.
Cesium Atomic Clock
47
A unique integer number that is used to encrypt the signal from that satellite.
Pseudorandom Noise
(PRN)
Code Number
48
A term associated with a table showing the position of a heavenly body on a number dates in a regular
sequence, in essence, an astronomical almanac. Ephemeris 49
Error in the receiver’s clock which affects the accuracy
of the time-difference measurement. Clock Bias Error
50
The Navstar control segment.
It consists of :
Fixed-location ground based monitor stations
Master Control Station
uplink transmitter
Operational Control System
51
It makes standard GPS more accurate. It works by cancelling out most of the natural and man-made errors
that creep into normal GPS measurements. Differential GPS