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7/28/2019 Emerging Trends in Satellite Technology and Applications Seminar Summary
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Emerging Trends in Satellite Technology and Applications
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EMERGING TRENDS IN SATELLITE TECHNOLOGY AND
APPLICATIONS
Anisiobi Chiagoziem E., 20061521273
COE 500 Level, EEE Department, FUTO
ABSTRACT
In the rapidly advancing world of technology today, technological innovations
have proved to lead the way to greater development. Satellite technology has
evolved over the years, bringing in more efficient and effective solutions which
are applicable to all areas of life. This seminar paper, in an attempt to present the
emerging trends in satellite technology and its applications, begins with its
evolution. It discusses the different trends in the evolution of satellite technology
since its emergence to the present day. It also presents the emerging trends in
satellite technology and its current and future applications.
Key words:LEO system, nanosatellites, in-space refuelling.ContentsABSTRACT .............................................................................................................................................. 1
1.0 INTRODUCTION .......................................................................................................................... 2
1.1 Satellite Overview ................................................................................................................... 2
1.2 Satellite Orbits ........................................................................................................................ 3
1.3 SATELLITE HISTORY ................................................................................................................. 4
2.0 EVOLUTION OF SATELLITE TECHNOLOGY THROUGH THE AGES.................................................... 6
3.0 EMERGING TRENDS IN SATELLITE TECHNOLOGY ......................................................................... 9
3.1 LEO Systems ...........................................................................................................................10
3.2 In-Space Refuelling .................................................................................................................11
3.3 Nanosatellites ........................................................................................................................11
3.4 Satellite News Gathering (SNG) ..............................................................................................12
4.0 EMERGING TRENDS IN SATELLITE APPLICATIONS .......................................................................12
5.0 CONCLUSIONS AND RECOMMENDATION ...................................................................................14
REFERENCES ..........................................................................................................................................14
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1.0 INTRODUCTION
The level of advancement in satellite technology is astonishing; especially when
one considers that the technology is barely 54 years old. As at the year 2010, the
industry was worth over a $100 billion.
The applications of satellite technology are far reaching, wide-ranging and all-
encompassing. Satellite telephony, mobile internet, satellite television, satellite
radio, marine navigation, global positioning, astronomy and cosmic studies,
weather forecasting, meteorological research, video conferencing, remote
sensing, data mining, agriculture, defence and advanced warning system just to
mention a few are some of the applications of satellite technology.
1.1 SATELLITE OVERVIEW
1.1.1 What is a satellite?
A satellite can be said to be any object purposely placed in orbit around Earth,
other planets, or the Sun for the purpose of collecting information or
communication via radio.
Since 1957 when the first satellite (sputnik 1) was launched by USSR, thousands
of satellites have been launched into earth's orbit (Encarta, 2009). These havechanged the scope of the communications industry, the military and scientific
research, among others.
1.1.2 TYPES OF SATELLITE
There are various types of satellites today, and they vary according to their
intended application.
a) Communications satellitesb) Weather satellitesc) Earth Observation satellitesd) Navigation satellitee) Military satellite (reconnaissance)f) Research and Scientific satellitea) Communications satellite: These satellites act as radio relay stations which
receive, amplify and retransmit information carried on specific microwave
frequencies back to the earth providing television, telefax, telephone,
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radio, and digital data links around the world. Examples are Intelsat series,
NigComSat-1R, TelStar series, Iridium satellites, etc.
b) Weather satellites: These satellites provide meteorologists with scientificdata to predict weather conditions and are equipped with advanced
instruments that provide advance warning of severe weather conditions.
Examples are TIROS 1 (NASA), GOES satellites (NASA), MeteoSat (EU) and
NOAA (USA).
c) Earth Observation (Remote Sensing) Satellites: These satellites allowscientists to gather valuable data about the earth's ecosystem.
d) Navigation satellites: These satellites provide the exact location of aperson, ship, aircraft, etc to within a few meters. Example GPS.
e) Military Satellites: These are satellites that are owned by various militarybodies and are both used for high security communication between
military sites and for advanced warning on missile attacks.
f) Research and Scientific Satellites: These are satellites used by scientists toobserve the Sun, Moon, other planets and their moons, stars and galaxies.
Examples are the Hubble Space Telescope and the Mars Global Surveyor.
1.2 SATELLITE ORBITS
1.2.1 What is an Orbit:
An orbit is the path that a satellite follows as it revolves around Earth.
The defining characteristics of an orbit are its shape, its altitude, and the angle it
makes with Earths equator. The altitude of an orbit determines how long the
satellite takes to circle Earth and how much of the planet is visible to the satelliteat any given time.
1.2.2 Types of Orbits
In terms of commercial satellites, there are three main categories of orbits:
a) Geostationary Equatorial Orbit (GEO)b) Medium Earth Orbit (MEO)
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Fig. 1.1: Geostationary orbit (22,282 miles or
35,786km). Courtesy of Intelsat.
Fig. 1.2: Medium Earth orbit (8,000 20,000).Courtesy of Intelsat.
Fig. 1.3: Low Earth orbit (500 2,000).
Courtesy of Intelsat.
c) Low Earth Orbit (LEO)a) Geostationary Equatorial Orbit (GEO): Also known as Geosynchronous
Orbit, 35,786 km above the earth.
The satellite travels in the samedirection and at the same speed as
the Earth's rotation on its axis,
taking 24 hours to complete a full
trip around the globe. As a result,
these satellites stay above one
point on Earths equator at all times.
b) Medium Earth Orbit (MEO):
8,000-20,000 km above the earth
These are elliptical orbits which are
used mostly by navigation and
communication satellites, such as
GPS (USA), GLONASS (Russia).
c) Low Earth Orbit (LEO): 500-
2,000 km above the earth
These orbits are much closer to the
Earth, requiring satellites to travel
at a very high speed in order to
avoid being pulled out of orbit by
Earth's gravity. As such, it isexceptionally good for transmitting
data, such as in Iridium and Globalstar
satellite systems.
Other orbits include Molniya orbit, Polar orbit, High Altitude Platform etc.
1.3 SATELLITE HISTORY
Table 1.1 Timeline of selected milestones of satellite history from 1945 - date.YEAR DETAILS
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1945 Arthur C. Clarke, a well known physicist and author, wrote his famous prophecy,
predicting GEO satellites.
1957
(Oct. 4)
Launch of first satellite, Sputnik 1, by USSR. It transmitted radio signal to earth on
20.005 and 40.002 MHz; had an orbit of 101.5 minutes and a lifetime of 90days.
1960 USA (NASA) launched Echo 1 & Echo 2 balloon satellites. They made use of passive
relaying of TV and telephone signals by reflection of signals off the metalized
surface of the balloon.
1963 Launching of Syncom-2 by USA/NASA, the first experimental geostationary
satellite.
1964 Syncom-3, launching of the first truly GEO satellite was used to relay the 1964
Olympic games from Tokyo, Japan. (It had 300 telephone circuits or 1 TV channel).
1965 Launching of the Early Bird (Intelsat-1) satellite, first commercial geostationary
communications satellite having 240 telephone circuits or 1 TV channel, providing asatellite link across the Atlantic ocean.
1965 Launching of Molniya-1 (USSR), a non-GEO satellite implementing an elliptical orbit
with 12 hours revolution. Beginning of TV transmission to small-sized receive earth
stations in USSR (29 Molniya were launched between 1965 and 1975).
1974 Launching of Symphonie-1 satellite (France, Germany). The first three-axis
stabilized geostationary communications satellite.
1976 Launching of Marisat Satellite-(USA), the first maritime communication Satellite.
1978 Start of Global Positioning System (GPS).
1982 Start of Global Orbiting Navigation Satellite System GLONASS (Russia).
1984 Beginning of operation of satellite business system (using VSAT with full
transmit/receive operation).
1997 Introduction of first non-GEO satellite (little LEO) satellite system.
1998 Mobile experiments using ACTS (Advanced Communications Technology Satellites)
2002-2005 Introduction of wideband personal mobile communications system
2005-2012 Launching of the Galileo project by the European Union. A civilian satellite
navigation satellite made up of 30 satellites.
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Fig 2.1 Evolution of Satellite Communications technology.Courtesy of Indian Space Research Agency (ISRA).
2.0 EVOLUTION OF SATELLITE TECHNOLOGY THROUGH THE AGES
Satellite technology has evolved through the ages, from the crude" and
elementary design of Sputnik 1, the very first satellite to the present day multi-
million dollar Intelsat New Dawn, a lot of changes and improvements has been
implemented in satellite design and technology. These changes come as a result
of improvement in satellite manufacture, improvements in electronic circuit
design, improvements in antenna design, improvements in transponder design, in
modulation technique, in launch vehicles, improvements in production simulation
and testing techniques, etc.
All these improvements have brought about tremendous development in satellite
technology, bringing about increased lifespan, communication handling capacity,
and efficiency etc.
2.1 The 1950s
In the early years of satellite technology, the satellites designed then were
ingenious, resulting from a great deal of intense work done by scientific institutes
and design bureaus. With no previous experience and lots of theoretical data, the
M. S. Khomyakov led design team launched Sputnik 1, the very first satellite on
October 4, 1957. It was a 585 mm sphere, having a pair of whip-like antennas and
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powered by 3 silver-zinc batteries. It transmitted a series of beep- beep sounds
via radio (at 20.005 and 40.005 MHz) as it orbited the earth every 101.5 minutes
at a height of. It lasted for 3 months.
2.2 The 1960s
The 60s saw NASA coming up with several satellite programs like Echo, TIROS,
Relay, TelStar, Syncom etc. and the USSR bringing up their Molniya series.
Structural Design: The satellites of this period were cylindrical and spin-stabilized
(drum shaped). Part of the drum rotates (50 100 rpm) and part is despun so
that an antenna mounted in this part is always facing the earth. The spinning part
is covered with solar cells while the despun part which contains the antennas andearth sensors rotates once with every circling of the earth.
Antenna: These satellites made use of omni-directional antennas with a global
spot beam. But in 1969, Intelsat-3 came up with directional antennas.
2.3 The 1970s
The 70s saw a major technological boost in satellite design and technology with
the concept of frequency re-use which was introduced by Intelsat-4a.
Structural design: The shape and design of satellites changed in this period with
the introduction of three-axis (or body) stabilization. The satellite is shaped like a
box with numerous appendages attached and is maintained in space by
stabilizing elements for each of the three-axis. This made it possible to deploy
very large solar arrays, and provided more despun surface to mount antennas (D.
J. Whalen, 2010).
Frequency Utilization: As a solution to the frequency utilization problem,
frequency re-use was developed. This involves separating the signals spatially, so
that the same frequency bands can be used to service physically separate
locations on earth. This period also saw the upcoming of multiple spot beam
communication.
2.4 The 1980s
The concept of dual polarization frequency re-use (or polarization discrimination)
was one of the major highlights of the decade. Signals on the same frequency are
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Fig 2.2 NASA ACTS Satellite
Fig. 2.3 Illustration of a laser Intersatellite link
by the Artemis satellite. (Courtesy of ESTECH)
transmitted by the satellite antennas through different transponders using two
orthogonal polarizations (i.e. horizontal and vertical) of the radio-frequency
wave. This makes it possible to use the same frequency band within the same
footprint. The Intelsat V satellites were the first to carry this.
2.5 The 1990s
This period saw greater
technological improvements in
satellite technology with the
launching of ACTS (Advanced
Communications Technology
Satellites) by NASA in 1993. These
satellites implemented the most
revolutionary breakthroughs in
satellite communications history,
being the first high-speed, all digital
communications satellite (www.nasa.gov,
2008). According to NASA, ACTS is a 21st
century space technology prototype that will permit the satellite industry to riseabove this frequency saturation and meet the growing need for wider, more
flexible bandwidth by moving into the virtually untapped Ka-band (30/20 GHz).
(http://acts.grc.nasa.gov).
Antenna: The concept of multiple hopping beam antennas came up in this period.
These antennas use small-diameter, tightly-focused multiple beams, and each can
be hopped from one site to another in milliseconds. (http://acts.grc.nasa.gov)
Transponders: One other technological
advancement introduced in this era is
on-board processing, as advancement
over bent-pipe (or simply frequency
translation) signal processing.
On-board processing allows dynamic
reallocation of unused bandwidth,
multi-beam frequency re-use, the
http://www.nasa.gov/http://www.nasa.gov/http://www.nasa.gov/http://acts.grc.nasa.gov/docs/SCAN_20010911161614.PDFhttp://acts.grc.nasa.gov/docs/SCAN_20010911161614.PDFhttp://acts.grc.nasa.gov/docs/SCAN_20010911161614.PDFhttp://acts.grc.nasa.gov/http://acts.grc.nasa.gov/http://acts.grc.nasa.gov/http://acts.grc.nasa.gov/http://acts.grc.nasa.gov/docs/SCAN_20010911161614.PDFhttp://www.nasa.gov/7/28/2019 Emerging Trends in Satellite Technology and Applications Seminar Summary
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Fig. 2.4 Interlinking of satellite
networks via Intersatellite link ISL
discarding of empty uplink time slots, increasing downlink efficiency, statistical
multiplexing, forward error correction, etc.
Another technological highlight of this era was the concept of Intersatellite links
(ISL). ISLs are employed to provide connections between earth stations in theservice area of one satellite to earth stations in the service area of another
satellite when neither of the satellites covers both sets of earth stations i.e. it
offers increased coverage.
In this technology, the connection between satellites is fully at space level and
the interfacing of the network formats and protocols have to be performed on
board the satellites. There are two
basic technologies for itsimplementation: microwave
transmission (22.55 -23.55 GHz; 32.0
33.0 GHz; 54.23 58.2 GHz and 59
64GHz) and optical transmission which
uses LASER beams to transmit data
between satellites.
2.6 The New Millennium
This has brought in a new era in satellite
technology. New technologies such as in-space refuelling, nano-satellites and an
increase in the use of advanced digital satellite processing and switching have
marked the first few years of the millennium.
3.0 EMERGING TRENDS IN SATELLITE TECHNOLOGYSince the year 2000, many new and cutting edge technologies have appeared on
the satellite scene. These technologies seem to be bringing in a new age in the
satellite era.
This chapter will highlight on some of the new trends that have shown up on the
scene and also some of the ones promising to emerge in the next 10 years.
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Fig. 3.1 Teledesic Network
3.1 LEO SYSTEMS
This is the use of networks of small satellites in low earth orbit (2,000 km or less)
to provide global voice and data communication. This concept came up as a result
of the problem of propagation delay (affecting voice and data communication)inherent in GEO satellites. These LEO systems are of three (3) types and are
distinguished by reference to their terrestrial counterparts: paging, cellular and
fibre.
Table 3.1: Low Earth Orbit systems.
System Type Little LEO Big LEO Broadband LEO
Examples ORBCOMM Iridium,
Globalstar
Teledesic,
Skybridge
Main applications Low bit rate data Mobile telephony High bit rate data
Terrestrial
counterpart
Paging Cellular telephony Fibre
These LEO satellite systems seem to be the solution to the provision of internet
and voice services to many parts of
the world. They provide relatively
cheaper global access to the
telecommunications infrastructure
currently available only in
advanced urban areas of the
developed world.
This is possible because of the
number and scale of operating
satellites that the companies are
promising (Iridium: 66 satellites,
Globalstar: 48 satellites, SkyBridge:
80 satellites).
The Iridium system (which is currently active) has
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Fig. 3.2 Delfi C3 (Launched in 2011)
11 satellites in six polar low earth orbital planes at 780 km.
They can be accessed by special telephones that communicate with these
satellites and that allow users access to the regular telephone network from
anywhere on the globe.
3.2 IN-SPACE REFUELLING
This is relatively, the latest trend in satellite technology. This involves the
refuelling of satellites by other space craft launched into space for this purpose.
In fact, the worlds first space refuelling station is to be launched by 2015.
This technology will enable spacecrafts to tank up in low earth orbit. With this
technology, smaller and cheaper rockets could be used for missions that would beoutside their weight class and larger rockets would have their capabilities
considerably enhanced. This could double the capacity of rocket launchers (S.
Cass & B. Sauser, 2009).
As of March 2011, Intelsat agreed to purchase half of a 2,000 kg propellant
payload that an MDA Corporation spacecraft satellite-servicing demonstration
project to refuel five Intelsat communications satellites. This is to increase the
lifetime of the satellites that are already near the end of their useful life (Intelsat,2011).
3.3 NANOSATELLITES
These are miniaturized or small satellites
(1 10kg). These nanosatellites are seen
by some technology experts to be the
future of satellite technology. They havelow weights and small sizes, they are
more agile and stable, their power
consumption is low, they serve as test
beds for future applications and
technologies and they have good
educational uses. They could be used in
the nearest future as robots to assemble
larger satellites in space (J. Bouwmeester, 2008).
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3.4 SATELLITE NEWS GATHERING (SNG)
It is the temporary and occasional transmission at short notice of television or
sound for broadcasting purposes, using highly portable or transportable uplink
earth stations. (ITU Handbook, 2002)
It is a recent application of satellite technology and it is being used by many
television broadcasting companies with global viewership. For most of the late
90s, SNG was limited to outdoor broadcasting trucks. But since the turn of the
millennium, a new trend has appeared on the broadcasting scene. This is the
videophone. Videophones, which are devices equipped with miniature video
cameras, rely on satellite links to transmit video as well as audio signals.
Television news organizations have adopted the use of videophones to coverbreaking news stories in remote areas (Encarta, 2009).
4.0 EMERGING TRENDS IN SATELLITE APPLICATIONS
The technological advancements in satellite technology have led to the
application of satellite technology in virtually every field.
Many of such applications started coming up in the 90s and some, in the new
millennium. Apart from the traditional applications of satellite in communications
(i.e. telephony and television), some of the present and emerging areas of
application include: Navigation, Medicine, Education, Satellite Messaging, Global
Positioning, Agriculture, Geodesy, Geo-informatics and monitoring, Remote
sensing, Telecommunication, Television, Internet services.
a) Navigation: Satellite technology has changed the accuracy and scope of
navigation in the last few years. With the high pinpointing accuracy of GPS (USA),
GLONASS (Russia), BeiDou (China), Galileo (Europe), marine navigation has
become easier and better.
b) Medicine: Satellites have also impacted hugely in the area of medicine.
Especially in Telemedicine (which allow remote surgeries between countries).
c) Education: Advancement in satellite technology has also influenced
education. Presently, many universities around the world have satellite
programmes as part of their school activities. Also, in some countries of the
world, distance learning via satellite connections is being implemented.
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d) Global Positioning Services: A GPS receiver is a small apparatus containing
the ability to determine navigational coordinates by triangulating the signals from
multiple geosynchronous satellites. GPS (USA), GLONASS (Russia), BeiDou (China),
Galileo (Europe) all provide this service. It can work well for pinpointing locations
anywhere on the earth.
e) Agriculture: The agriculture industry has also taken advantage of satellite
technology, and GPS in particular for precision farming.This makes use of GPS
services for yield mapping (where GPS is attached to harvesting equipment and is
used to measure and map precisely, the yielding areas of a farmland), soil
mapping, tillage adjustments, seeding, etc. It is increasingly being used by the
Department of Agriculture on Prince Edward Island, Canada.
f) Geo-informatics and Monitoring: With the emergence of highly
specialised weather satellites, the scope of weather forecasting and predicting
has gone into an entirely new level. These weather satellites send information of
the weather condition, cloud formation and motion, tidal waves motion and
global wind patterns.
g) Remote Sensing: This is the process of obtaining information about land,
water, or an object, without any physical contact between the sensor and thesubject of analysis (Encarta, 2009).Remote sensing satellites carry all sorts of
sensors such as very high-resolution cameras, multispectral scanners (MSSs), very
high resolution radiometers (VHRRs), thermatic mapper (TM) and a synthetic
aperture radar (SAR) amongst others for sensing purposes (Maini, 2007).
h) Television: Satellites have been used extensively for television purposes
since the 1964 Olympic Games. Presently, many television stations have a global
audience connected via satellite. Also, with the emergence of direct broadcastsatellites in the 90s, direct transmission of television signals to homes having
small dishes is now possible.
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5.0 CONCLUSIONS AND RECOMMENDATION
5.1 CONCLUSIONS
The satellite scene is a rapidly advancing field with newer trends appearing every
few years. These developments will continue as mankind keeps on pushing the
borders of technology. On-going scientific research in many nations (USA, Russia,
China, Japan, etc) is working on technological innovations and cutting edge
solutions to move satellite communications forward.
Up till this point, many efforts are being made to remove the constraints to
satellite technology such as size of space craft, frequencies, weight of satellites,
efficiency and availability of launch vehicles, range of available frequencies, etc.
And as all these constraints are being individually removed by hard pushing space
laboratories, satellites will take on a new look and feel; its design more dynamic;
and its applications more encompassing.
5.2 RECOMMENDATIONS
Based on the foregoing, it is necessary for more researches and studies to be
conducted in the field of satellite technology, to enable further breakthroughs in
the field.
Particularly, I recommend that Nigerians should harness these applications of
satellite technology to provide solution to the problems facing the country,
especially in the areas of education, data communications, navigation, weather
forecasting, etc.
Also, Nigerian Universities should become actively involved in satellite education,
research and development so as to enhance students knowledge, and to move
Nigeria, as a country further into the satellite age.
REFERENCES
1. Bouwmeester J., (2008), Advancing Nano-Satellite Platforms: The Delfi
Program.Paper IAC-08-B4.4.B9, International Astronautical Congress, Glasgow,
Scotland.
2. Kruczynski L. R, (2009), Artificial Satellite, Microsoft Encarta 2009,
Redmond, Washington, USA.
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3. Mark A. Sturza, (1999) Architecture of the Teledesic Satellite System.
Teledesic Corporation, Washington, USA.
4. Christopher Redding, (1999), Overview of LEO Satellite Systems.1999
International Symposium on Advanced Radio Technologies, Colorado, USA.
5. Maini A. K. and Agrawal V., (2007), Satellite Technology: Principles and
Applications.John Wiley & Sons, Ltd, West Sussex, England.
8. David J. Whalen (2010) Communications Satellites: Making the Global
Village Possible.Retrieved 3 June, 2011 fromhttp://www.history.nasa.gov
8. Das Gupta A. R. and Das Gupta K. S., (2003),The Emerging Trends in
Satellite and Wireless Communications Technologies.Indian Space ResearchOrganization, Ahmedabad, Gujarat, India.
9. International Telecommunication Union, 3rd
ed. (2002), Handbook on
Satellite Communications.John Wiley & Sons, New York, USA.
http://www.history.nasa.gov/http://www.history.nasa.gov/http://www.history.nasa.gov/http://www.history.nasa.gov/