satellite communication
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Satellite TelecommunicationsOverview
Ali Mohseni Ahoueia.ahouei@gmail.com
Satellite History
VSAT
Satellite Technologies
Main Concept
Content
Satellite History
• 1911 The Initiate Concept of Radio Propagation through Space • 1945 The first theory of Geostationary Satellites(GEO)• 1957 Spotnik-1 Pioneer of Satellite Competition lunched by Russia.
(LEO)
Satellite History
2006• The First introduction of Telecom Communication via Satellite by USA• 1960 The First Military Satellite Lunched by USA• 1960 Echo-1 The first passive Satellite lunched by USA.(LEO)
Satellite History
2006• Close competition between USA & USSR during 1958~1961• The First Britain-Canadian Satellite lunched in 1962 • 1962 The birth of first Telstars, a Cooperation among AT&T, Bell Telephone
Laboratories, NASA, the British General Post Office, and the French National PTT (Post, Telegraph & Telecom Office) (LEO)
Satellite History• 1962 Syncom1 as a first lunched Geo Satellite By USA was Introduced to the
world but lost on the way.• 1963 Syncom2 finally lunched in Geo Orbit
Syncom 2
Television pictures were broadcast via satellite for the first time with NHK providing the globe with the pictures and sound of the 1964 Tokyo Games. The pictures were taken live in Tokyo and could be seen simultaneously via the Syncom III satellite in more than 20 U.S. states and Canada.
Satellite History
VSAT
Satellite Technologies
Main Concept
What is the SatelliteIn the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavor Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon.
They are located in 3 orbits:LEO: Low Earth Orbit.MEO: Medium Earth OrbitGEO: Geostationary Earth Orbit
LEO Satellites & Services • Located at the distance of 400-1600 Km
Satellites:• SkyBridg• Iridium• Globalsta• Orbcom
Services:
• Mostly for Satellite Mobile Communication (GSM Over Satellite) due to the shorter distance and shorter delay
MEO Satellites & Services • Located at the distance of 8000-16000 Km
• More coverage and delay
Satellites:• Akebono • Alouette 2• Navstar
Services:
• Mostly for Navigation. Global Positioning System(GPS).
• At list 3 satellites are needed to get Long & Lat
Geostationary Satellites & Services • All Geo Satellites Located On the Equator line
(Latiyude always is 0°) at the distance of 35800Km.
• Most of the Weather & Communication Satellites lunched into Geo Orbit
• Their rotation is fixed as the Earth revolving 0.5s Delay
Geostationary Satellites & Services • Each satellite covers 40% of the Earth• Theoretically 3 geostaionary satellites provides
100% earth coverage
Satellites:• HotBird• Badr • NileSat• EuroBird• Eutelsat
Satellite Services MSS Mobile Satellite Services
FSS Fixed Satellite ServicesDBS Digital Broad Cats ServicesTSS Telecommunication Satellite Services
We aim to analyze FSS
BW Fragment
TransponderVirtual division of Bandwidth over satellite Amplifier and translator
NE
Wskies-N
SS
6
Polarization
Cross-PolV: VerticalH: Horizontal
C: Co-Pol
Beams
Satellite FootprintA spot beam, in telecommunications parlance, is a satellite signal that is specially concentrated in power
Point a Satellite Dish
Satellite Positioning & Pointing
20.3°w0°N
115°E0°NHotbird
13°E0°N
Meridian
Equator
0°0°
Example:Longitude Of Tehran: 51° E
If you are going to point on Hotbird:51°- 13°= 38°E
38°E
Tehran
Long:51° E
Lat:35°N
Point a Satellite Dish
Satellite Positioning & Pointing Example:If you are in Tehran and going to point on Hotbird:Elevation must be : 32.5°
38°E
32.5°
X
Y
Arc tan(Y/X)>32.5°Arc tan(Y/X)<32.5°
Satellite History
VSAT
Satellite Technologies
Main Concept
VSAT(Very Small Aperture Terminal)
VSAT:Dish antenna that is smaller than 3 meters
Frequency Bands
C band
Frequency BandsL band 1 to 2 GHz
S band 2 to 4 GHz
C band 4 to 8 GHz
X band 8 to 12 GHz
Ku band 12 to 18 GHz
K band 18 to 26.5 GHz
Ka band 26.5 to 40 GHz
5.925 to 6.42GHz (
V/H/C)3.7 to 4.2 GHz (V/H/C)
10.95
-11.7
GHz(V
/H/C
)
14.0 - 14.5 GHz(V/H/C)
λ= C/fKu band
<5m<5m
>3m>3m
Satellite History
VSAT
Satellite Technologies
Main Concept
Satellite Access Technology
SCPC / SCPC TDM / TDMAMF-TDMADVBDVB/SCPCDVB-RCSMCPC / PDMA
Satellite Access TechnologySCPC / SCPC
Satellite Access Technology
TDM / TDMA
Remote 2
Remote 1
Remote3
R1
R3
R2
R1
R1
R2
R2
R3
R3
Hub
Satellite Access Technology
Remote 3
Remote 1
Remote 4
HubRemote 2
MF-TDMA
Satellite Access Technology
DVB/SCPC
HubRemote 2
Remote 3
Remote 1
Satellite Access Technology
Remote 3
Remote 1
Remote 4
Hub Remote 2
DVB/RCS
Satellite Access TechnologyMCPC/PDMA
Thanks!
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