This is the summary notes of the important terms and concepts in Chapter 26 of the book "Electronic Communications System" by Wayne Tomasi. The notes are properly synchronized and concise for much better understanding of the book. Make sure to familiarize this review notes to increase the chance of passing the ECE Board Exam.
CHAPTER 26 |
SATELLITE MULTIPLE ACCESSING ARRANGEMENTS |
Items |
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”. |
|
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 direction with respect to familiar, significant landmarks such as railroad tracks, water towers, barns, mountains and bodies of water. |
Piloting |
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 |
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