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STRATELLITE A Technical Seminar Report submitted in partial fulfillment of the requirements For the award of the degree of BACHELOR OF TECHNOLOGY IN ELECTRONICS AND COMMUNICATION ENGINEERING By D.NARESH 10QQ1A0466 KITE COLLEGE OF PROFESSIONAL ENGINEERING SCIENCES (Affiliated to JNTU, Hyderabad) SHABAD R.R. DISTRICT – 509217 2013-2014

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Page 1: stratellite document

STRATELLITEA Technical Seminar Report submitted in partial fulfillment of the

requirementsFor the award of the degree of

BACHELOR OF TECHNOLOGYIN

ELECTRONICS AND COMMUNICATION ENGINEERING

By D.NARESH 10QQ1A0466

KITE COLLEGE OF PROFESSIONAL ENGINEERING SCIENCES

(Affiliated to JNTU, Hyderabad) SHABAD R.R. DISTRICT – 509217

2013-2014

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ACKNOWLEDGEMENT

I take this opportunity to remember and acknowledge the cooperation, good will and

support both moral and technical extended by several individuals out of which this technical

seminar has evolved. I shall always cherish our association with them.

I greatly thankful to Dr. K. SOUNDARARAJAN, Principal of our college, for extending

his help. I shall forever cherish my association with him for his encouragement. Perennial

approachability, absolute freedom of thought and action.

I greatly thankful to Mr. K.J. ARVIND CHARY, In-Charge , Head Of The Department,

Department of Electronics And Communication Engineering, for his enthusiastic assistance.I

have immense pleasure in expressing my thanks and deep sense of gratitude for his guidance

and assistance offered in an amiable and pleasant manner through my technical seminar.

A lot of thanks to other faculty members of the department who gave their valuable

suggestions at different stages of my technical seminar.

I am very much thankful to our parents who helped me with utmost friendliness and

warmth always. They kept my spirit flying high and persistently encouraged me to undertake and

complete this technical seminar.

N.RAMU

(10QQ1A0444)

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ACKNOWLEDGEMENT

I take this opportunity to remember and acknowledge the cooperation, good will and

support both moral and technical extended by several individuals out of which this technical

seminar has evolved. I shall always cherish our association with them.

I greatly thankful to Dr. K. SOUNDARARAJAN, Principal of our college, for extending

his help. I shall forever cherish my association with him for his encouragement. Perennial

approachability, absolute freedom of thought and action.

I greatly thankful to Mr. K.J. ARVIND CHARY, In-Charge , Head Of The Department,

Department of Electronics And Communication Engineering, for his enthusiastic assistance.I

have immense pleasure in expressing my thanks and deep sense of gratitude for his guidance

and assistance offered in an amiable and pleasant manner through my technical seminar.

A lot of thanks to other faculty members of the department who gave their valuable

suggestions at different stages of my technical seminar.

I am very much thankful to our parents who helped me with utmost friendliness and

warmth always. They kept my spirit flying high and persistently encouraged me to undertake and

complete this technical seminar.

N.RAMU

(10QQ1A0444)

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Index

Acknowledgement

List of figures

AbstractChapter 1: Introduction

1.1 Introduction 1

1.2 4generation 1

1.3 4g mobile communicatin 2

1.3.1 broad-band wireless systems 2

1.3.2 intelligent transport systems 3

1.3.3 high altitude stratospheric platform station systems (haps) 4

chapter 2: stratellite

2.1 stratellite 6

2.2 construction of stratellite 7

2.3 specifications 9

2.4 stratellite technology and advantages 9

2.5 drawbacks of satellites 10

2.6 services 11

2.7 applications it enables 11

2.8 stratellites and telecommunications 12

2.9 stratellite challenges and business opportunities 13

2.10 marketability and costs 14

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chapter 3: satellites

3.1 satellite 15

3.2 what are satellites 15

3.3 how do satellites get into space 16

3.4 what are satellites used for 16

3.5 how do satellites work in space 16

CONCLUSION 18

REFERENCES 19

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ABSTRACT

Wireless communication is simply data communication without the use of landlines. This may

involve cellular telephone, two-way radio, fixed wireless (broadband wireless), laser (freespace optics)

or satellite communications. Mobile wireless technologies are going to act as glue towards bringing

together the wired and wireless to share and distribute information seamlessly across each other’s areas

of reference.

The paper firstly introduces the wireless communications and then switches to fourth

generation in wireless communications.

The paper then discusses about High Altitude Airships, the “STRATELLITES” which are actually

unmanned Kelvar balloons filled with helium which are used instead of towers for wireless

communication, each of which replace hundreds of towers and reduce the cost of wireless

communications. They also overcome the disadvantage of simple towers which could not provide

proper coverage in the hilly areas.

N.RAMU

10QQ1A0444

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Chapter 1

INTRODUCTION TO STRATELLITE

1.1 INTRODUCTION

Wireless communication is simply data communication without the use of landlines.

This may involve cellular telephone, two-way radio, fixed wireless (broadband wireless), laser

(freespace optics) or satellite communication systems. Mobile wireless technologies are going to

act as glue towards bringing together the wired and wireless to share and distribute information

seamlessly across each other’s areas of reference.

Since from the beginning of wireless communications, there have been a number of

developments in each generation. Considering the future generation of wireless communication

i.e; 4G.

1.2 4GENERATION

HAPS have the potential to become the third communications infrastructure after

terrestrial and satellite communications. The platforms keep their positions at about 20 km high

in the stratosphere. By optical intercommunication links, they make a mesh-like network in the

sky. A broadband access link is the link between the platform station and the user station.

The typical bit rate of the access link is 25 Mb/s for most fixed and portable

terminals, while a several hundred megabits per second link is available for limited fixed

terminals with antennas larger than the typical ones. Because of using millimeter-wave bands, a

small antenna with high gain is feasible. For example, a bit rate of 144 kb/s can be provided for

vehicles by only a 5 cm dish antenna with 20 dB gain

1.3 4G MOBILE COMMUNICATION

Some of the systems for future mobile communications are:

1. Broad-Band Wireless Systems

2. Intelligent Transport Systems

3. High Altitude Stratospheric Platform Station Systems.

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1.3.1 BROAD-BAND WIRELESS SYSTEMS

Wireless networks can feature data rates roughly equivalent to some wired networks,

such as that of asymmetric digital subscriber line (ADSL) or a cable modem. Wireless networks

can also be symmetrical, meaning the same rate in both directions (downstream and upstream),

which is most commonly associated with fixed wireless networks. A fixed wireless network link

is a stationary terrestrial wireless connection, which can support higher data rates for the same

power as mobile or satellite systems.

Few wireless Internet service providers (WISPs) provide download speeds of over 100

Mbit/s; most broadband wireless access (BWA) services are estimated to have a range of 50 km

(31 mi) from a tower. Technologies used include LMDS and MMDS, as well as heavy use of the

ISM bands and one particular access technology was standardized by IEEE 802.16, with

products known as WiMAX.

WiMAX is highly popular in Europe but has not met full acceptance in the United States

because cost of deployment does not meet return on investment figures. In 2005 the Federal

Communications Commission adopted a Report and Order that revised the FCC’s rules to open

the 3650 MHz band for terrestrial wireless broadband operations

1.3.2 INTELLIGENT TRANSPORT SYSTEMS

Although ITS may refer to all modes of transport, EU Directive 2010/40/EU of 7 July

2010 on the framework for the deployment of intelligent transport systems in the field of road

transport and for interfaces with other modes of transport defines ITS as systems in which

information and communication technologies are applied in the field of road transport, including

infrastructure, vehicles and users, and in traffic management and mobility management, as well

as for interfaces with other modes of transport.

Recent governmental activity in the area of ITS – specifically in the United

States – is further motivated by an increasing focus on homeland security. Many of the proposed

ITS systems also involve surveillance of the roadways, which is a priority of homeland security.

Funding of many systems comes either directly through homeland security organisations or with

their approval. Further, ITS can play a role in the rapid mass evacuation of people in urban

centres after large casualty events such as a result of a natural disaster or threat. Much of the

infrastructure and planning involved with ITS parallels the need for homeland security systems.

In the developing world, the migration from rural to urbanized habitats has

progressed differently. Many areas of the developing world have urbanised without significant

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motorisation and the formation of suburbs. A small portion of the population can afford

automobiles, but the automobiles greatly increase congestion in these multimodal transportation

systems. They also produce considerable of air pollution, pose a significant safety risk, and

exacerbate feelings of inequities in the society. High-population density could be supported by a

multimodal system of walking, bicycle transportation, motorcycles, buses, and trains

INTELLIGENT TRANSPORT TECHNOLOGIES

Intelligent transport systems vary in technologies applied, from basic

management systems such as car navigation; traffic signal control systems; container

management systems; variable message signs; automatic number plate recognition or speed

cameras to monitor applications, such as security CCTV systems; and to more advanced

applications that integrate live data and feedback from a number of other sources, such as

parking guidance and information systems; weather information; bridge de-icing (US deicing)

systems; and the like. Additionally, predictive techniques are being developed to allow advanced

modelling and comparison with historical baseline data. Some of these technologies are

described in the following sections.

1.3.3 HIGH ALTITUDE STRATOSPHERIC PLATFORM STATION

SYSTEMS (HAPS)

HAPS has the potential to become the third communications infrastructure

after terrestrial and satellite communications. The platforms keep their positions at about 20 km

high in the stratosphere. By optical intercommunication links, they make a mesh-like network in

the sky. A broadband access link is the link between the platform station and the user station.

The typical bit rate of the access link is 25 Mb/s for most fixed and portable

terminals, while a several hundred megabits per second link is available for limited fixed

terminals with antennas larger than the typical ones. Because of using millimeter-wave bands, a

small antenna with high gain is feasible. For example, a bit rate of 144 kb/s can be provided for

vehicles by only a 5 cm dish antenna with 20 dB gain.

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Simple HAPS System

Figure 1.1 HAPS System

Fig 1.1 Simple HAPS System

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Chapter 2

STRATELLITE

2.1 STRATELLITE

A “stratellite” is a high-altitude airship (HAA) “25 times larger than the

Goodyear blimp” employed much like a satellite for remote sensing, navigation, and

communications. Instead of being stationed on orbit, stratellites are positioned in the

stratosphere approximately 13 miles above the Earth.

This altitude places the airships above both commercial air traffic and weather

effects but significantly lower than standard low earth orbits. From this height stratellites can

service a 300,000-square-mile-area. The North American Aerospace Defense Command

(NORAD) projects that eleven such airships could provide radar coverage of the entire

maritime and southern borders of the United States.

Fig 2.1 STRATELLITE

2.2 Construction Of Stratellite

The initial Stratellite was 188 feet long, 60 feet wide and 42 feet high. It is provided

with a new steering method which uses a hybrid electric system that drives large,

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slow-turning propellers. This gives the airship helicopter-like agility by being able

to move both up and down, and side to side.

The outside layer, or "envelope," is made out of a high-tech material

called Spectra - a fabric used in bullet-proof vests and parts of space shuttles.

Spectra contains fibre 10 times as strong as steel of the same weight and has the

unique feature of being easy to cut but virtually impossible to tear.

Fig 2.2 Construction of Stratellite

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Fig 2.3 srtatellite

The inside layer, made from a thin but strong polyester film called Mylar, is fitted

inside the envelope and filled with a mixture of helium and air as helium is an inert

gas and is therefore not flammable. With this design, the helium expands as the

airship rises, forcing air out and lifting the airship. The cycle continues, allowing

the airship to gain more and more altitude until the helium has expanded to fill the

envelope completely. Because the pressure is so low inside the envelope, a puncture

would only result in a very slow leak, taking a long time to totally deflate. 4,000

pounds, and later models are expected to carry over 20,000 pounds of radars and other remote

imaging equipment, navigational aids, and telecommunications relays. Stratellites are planned to

remain on station for a year at a time and will cost a fifth as much as a comparable satellite.

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2.3 SPECIFICATIONS

GENERAL CHARACTERISTICS

a. Length: 245 ft in (75 m)

b. Width: 145 ft in (44 m)

c. Height: 87 ft in (26.5 m)

d. Volume: 1.3 million ft3 (420,000 m3)

PERFORMANCE

a. Service ceiling: 70,000 ft (21,000 m)

b. Dual envelopes, made of Dynamo (sometimes called Spectra)

c. Navigation: 6 onboard GPS units connected to the ship's engines

d. Payload capacity: 3,000 lb (1,451 kg)

e. Cruising altitude: 65,000 ft (20,000 m)

f. Lifting gas: Helium and Nitrogen

g. Line-of-sight: 300,000 mile² (480,000 km²)

h. Maximum duration aloft: 18 months

2.4 STRATELLITE TECHNOLOGY AND ADVANTAGES

Stratellites are actually unmanned Kevlar balloons filled with helium. They use thin-

film photovoltaic cells sprayed on their surfaces to generate electricity, which drives propellers

that work with GPS technology to keep the stratellite positioned over one spot on the Earth’s

surface. Prototype airships are projected to carry payloads as large as 4,000 pounds, and later

models are expected to carry over 20,000 pounds of radars and other remote imaging equipment,

navigational aids, and telecommunications relays. Stratellites are planned to remain on station for

a year at a time and will cost a fifth as much as a comparable satellit

a. Decreases Signal latency

b. Less expensive to launch

c. Service an area of 300,000 square-miles

d. Two-way high speed data communication

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e. High speed broad-band access even in remote area.

f. For a country two stratellites are enough instead of thousands of towers

2.5 DRAWBACKS OF SATELLITES

These firms are becoming involved with stratellites because they avoid the two main

drawbacks of satellites. The first is signal latency, which can cause problems in establishing

broadband links.Most telecommunications satellites are in geostationary orbit to remain above a

certain point on the Earth’s surface. That orbit, however, is 22,240 miles above the Earth, (i.e; in

the area called CLARKE’S BELT), which means that a signal going up to the satellite(uplink)

and back to the Earth(downlink) travels nearly 45,000 miles, which equates to about a quarter of

a second delay. Even users of satellite voice links notice the delay.

Fig 2.4 stratellite transmission

The second drawback is that satellites are in space, requiring expensive space launches, an

additional level of regulation by national space authorities, and an orbital allotment by the

International Telecommunications Union (ITU). Stratellites remain in national airspace and are

Stratellites remain in national airspace and are therefore not subject to these licensing and

technology requirements. However, they do make use of space technology and, as stated above,

are in development by at least one space industry firm.

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2.6 SERVICES At an altitude of 13 miles, each Stratellite will have clear line-of-site communications

capability to an entire major metropolitan area as well as being able to provide coverage across

major rural areas. “The idea, if successful, would be revolutionary for underserved areas where

broadband is not as popular because the areas are too expensive to reach by telephone or cable

network.” “Existing satellites provide easy ‘download’ capabilities, but because of their high

altitude are not practical or commercially viable for a ‘two-way’ high speed data communication.

The Stratellite will allow subscribers to easily communicate in ‘both directions’ using readily

available wireless technology.”

This means that subscribers can send and receive information using

the network, like the current broadband internet system but, without the wires, cables and

cellular towers.

2.7 APPLICATIONS IT ENABLES

Once a Stratellite network is in place, it will provide a national

broadband wireless network that will provide voice, video, and broadband internet access

to all parts of the country. By linking several Stratellites together they can provide a

wireless broadband network that will cover thousands of miles. With a Stratellite

network, subscribers will be able to sit in their homes and be connected on their laptops

to the internet at high speed. If subscribers need to go to the office, across town, or even

to another city, they can close their laptop and take off, reopening the laptop at their new

destination and still be connected to the internet. In environmental disasters

telecommunication breaks down within seconds, Re-installation of the infrastructure

takes weeks or months. The Stratellite can be used as a floating mobile

telecommunication station for all telecommunication purposes and the transmission of

temporary data communication, telecommunication and TV-programs as well as long-

term missions over metropolitan cities.This would allow subscribers the ease of not

having to find local access numbers, tie up phone lines, deal with modem hassles, and

more importantly, slow speeds. In addition to internet use, “proposed

telecommunications uses include cellular, 3G/4G mobile, MMDS, fixed wireless

telephony, HDTV, real-time surveillance and others.

2.8 STRATELLITES AND TELECOMMUNICATIONS

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Stratellites offer a window of telecommunications opportunity. Effectively, a

Stratellite positioned over a major metropolitan area could act as a cell tower thirteen miles high.

A Stratellite, equipped with the appropriate transponders, could manage the wireless needs of

that entire metropolitan area. Transponder access could be leased to broadband users such as

Internet Service Providers (ISP’s), cell phone companies, television networks, radio stations,

various levels of government, and to corporations with large broadband requirements. These

consumers could then resell access to end users, for residential Internet access, for example.

None of this type of business or wireless use is innovative, so existing regulatory

schemes and business models cover Stratellite communications. In fact, Stratellites employed in

this manner would make use of existing spectrum allocations, at least initially, and not require

expensive bandwidth acquisition. Additionally, the marketing of such links would be virtually

identical to current marketing. By increasing the utility and availability of the type of link that

has, until now, been restricted to satellites, firms can bring broadband links to new areas, provide

for increased usage, and service larger markets without any fundamental change in operations.

2.9 STRATELLITE CHALLENGES AND BUSINESS

OPPORTUNITIES Though the opportunities for increasing broadband links and for profit are

enormous, Stratellites are still in their infancy. They present several problems that have yet to be

fully addressed. The public may be concerned about such large, unmanned payloads stationed

above metropolitan areas and recent developments in sub-orbital flight could eventually lead to

traffic problems in the stratosphere. More importantly, critics question whether technology really

exists that can keep Stratellites on station for such long periods of time. Once these concerns are

overcome and working Stratellites are available, the potential exists for vastly expanding

broadband links.

Some telecommunications providers, such as Sanswire Technologies, have recognized this

marketing opportunity and already have formed joint ventures with the space industry and

balloon-makers. However, in addition to marketing, Stratellites will require ground control and

maintenance, and used Stratellites will require refurbishment before redeployment, tasks which

the manufacturers and marketers may well lack the capacity or desire to perform.

As broadband requirements increase, Stratellites present a mobile, low-cost, high-

capacity alternative to satellite relays and cell towers. In remote areas, over the oceans, in

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metropolises, and in areas stricken by disaster, Stratellites will immediately provide broadband

access and broadcast capacity. Prototypes are in testing and development now.

The potential benefits of Stratellites are so great that it is not a question of whether the

technological problems will be solved, but when. Soon Stratellites will be bringing the Internet,

cell phone access, radar monitoring, and radio and television service to all corners of the globe.

2.10 MARKETABILITY AND COSTS

In addition to providing “two-way” communication, Stratellites make more sense

than wireless systems and satellites: (1) there is no use of huge ugly cellular towers, since they

are in orbit, and (2) they are far cheaper to launch, maintain and upgrade than satellites.

However, there are still two big concerns: if Stratellites will actually work, and their cost as

launching things into space (or near space) can be costly.

Using wireless equipment, a company would have to install over 14,000 cellular towers to cover

the same area as Snaswire’s proposed Stratellite based national wireless network. That means that

there will be over 14,000 more ugly towers to hide. In addition, this technology will make the need for

expensive cabling obsolete.

“One of the many advantages our High Altitude Airships have over satellite technology is that

the payload can easily be recovered, upgraded, and re-launched in a matter of hours.” Thus, each

airship can be retrieved and re-used.

Even if these costs are kept down Stratellites do not come without problems or doubters. They

have to float inside 200 to 300 meter box and that’s hard for an airship. After you solve that problem,

you have to create a service that can perform better and cheaper than DSL. In addition, Stratellites are

susceptible to the same kinds of interferences that satellite systems currently are.

Overall, the idea of a Stratellite wireless network seem to be marketable in the sense that

they would be more cost effective than satellites and cellular towers, and with the proper testing

they potentially have the ability to turn the whole country in one giant hot spot. This is

something that from judging by the popularity and use of “hotspots” the nation is ready for.

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Chapter 3

SATELLITES

3.1 SATELLITEHow does a television signal get to the other side of the world in seconds? What tells ships

exactly where they are in the middle of the ocean? How do we get warning that storms are

coming? Satellites do all these things and more

Fig 3.1 satellite

3.2 WHAT ARE SATELLITES?

Satellites are objects in outer space that fly around planets in circular paths called orbits. Artificial satellites are made by people. Thousands of satellites are zooming around our planet right now.

The Soviet Union launched the first artificial satellite, Sputnik 1, in 1957. Sputnik 1 broadcasted a steady signal of beeps. It circled Earth for three months and then fell back into the atmosphere and burned up. The atmosphere is the air that surrounds Earth.

3.3 HOW DO SATELLITES GET INTO SPACE?

Satellites need to reach a height of at least 120 miles (200 kilometers) to orbit. They also need to travel faster than 18,000 miles per hour (29,000 kilometers per hour). A satellite any lower or

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slower would soon fall back down to Earth. It takes a rocket to bring satellites up to that height and speed.

Most satellites are launched from the ground. Some small satellites can be launched from high-flying planes. This uses less fuel.

Other satellites are launched using a space shuttle or other piloted rocket. This way, astronauts on the space shuttle can make sure the satellite is working and gets into the right orbit.

3.4 WHAT ARE SATELLITES USED FOR?

Satellites are used for a great many things. Communications satellites beam TV, radio, and telephone signals all around the world. Navigational satellites help people know where they are and get where they are going. Weather satellites take pictures of clouds and storms from above to help make weather forecasts. Spy satellites look down and snoop on other countries. Other satellites help scientists to study Earth and other planets.

3.5 HOW DO SATELLITES WORK IN SPACE?

Space is a difficult place to be. You can’t plug in a cord in outer space, so satellites need to take a power source with them. It’s hard to get satellites pointed in the right direction because there’s nothing to turn them with. Satellites need to work in the freezing cold of Earth’s shadow as well as in the blazing heat of the Sun’s rays. They also need to be tough enough to survive collisions with tiny asteroids (space rocks)!

Most satellites use both power from the Sun and batteries to work. They catch the Sun’s energy using large flat solar panels. Satellites keep these panels pointed at the Sun. They use batteries when the Sun doesn’t shine on them.

Satellites can stay pointed in the right direction using small rockets called attitude thrusters. They can also use instruments called gyroscopes. Sometimes magnets on board the satellite can push against the magnetic field of Earth to aim the satellite correctly.

No air flows past satellites to cool them. To keep from getting too hot in the Sun, satellites have panels that open and close. This lets heat escape. Satellites often spin so the Sun doesn’t make one side so hot that it melts.

Satellites also need to be made from strong materials in case tiny asteroids hit them. They need materials that don’t become brittle in the cold and the harsh radiation of space.

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CONCLUSION

Stratelites provide the required facilities of wireless communication more Stratelites provide the required facilities of wireless communication more

efficiently than the ordinary towers. The Stratellite will allow subscribers to easily communicateefficiently than the ordinary towers. The Stratellite will allow subscribers to easily communicate

in ‘both directions’ using readily available wireless technology.” They minimise the cost ofin ‘both directions’ using readily available wireless technology.” They minimise the cost of

communication.communication.

Stratellites present a mobile, low-cost, high-capacity alternative to satellite relays and Stratellites present a mobile, low-cost, high-capacity alternative to satellite relays and

cell towers. Once the defects of Stratellites have been overcome and become more reliable, theycell towers. Once the defects of Stratellites have been overcome and become more reliable, they

play a vital role in the future generation wireless communication.play a vital role in the future generation wireless communication.

Once the defects of Once the defects of   Stratellites have been overcome and becomeStratellites have been overcome and become

more reliable, they play a vital role in the future generation wireless communication.This is amore reliable, they play a vital role in the future generation wireless communication.This is a

promising technology that could combine the best of Satellite and wired Internet - fast with lowpromising technology that could combine the best of Satellite and wired Internet - fast with low

latency and hugely widespread, at least in theory.Probably the most "far out there" concept inlatency and hugely widespread, at least in theory.Probably the most "far out there" concept in

this roundup, Stratellite is actually much closer to reality than what you may think.this roundup, Stratellite is actually much closer to reality than what you may think.

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REFERENCES

1. www.google.co.in

2. www.yahoosearch.com

3. Howstuffworks.com

4. 21st Century Airships, Inc., High Altitude Platy http://www.21stcenturyairships.com/

5. Geostationary Orbits, in Wikipedia, at http://en.wikipedia.org/wiki/Geostationary_orbit (last

accessed Sept. 28, 2004).

 6. TWUF, Broadband Takes to the Skiesrt

Tec dirt, Get Your Wireless Broadband By Stratellite,