i want to share my views on airship as low cost alternatives to communication satellite we have only pdf of this topic because i searched a lot i didn't find any ppt so i make it and presented well in my college so i am sharing this ppt to present easily and for infromation
2. CONTENTS
Introduction.
Need For High Altitude Communication Platform.
Limitations of Satellites and Tower networking.
Aerial Communication Platforms.
Benefits of HAPs over other systems.
Airships for HAPS.
Benefits of Airships as HAPs.
Problems / Challenges faced by Airship HAPs.
Current Developments Of Airship HAPs.
Key facts about ATG StratSat platform.
Conclusion.
References.
3. What is an Airship?
Airship is an aircraft that consists of a cigar-shaped gas bag, or
envelope, filled with a lighter-than-air gas to provide lift, a propulsion
system, a steering mechanism, and a gondola accommodating
passengers, crew, and cargo.
What is a satellite ?
Satellite is an artificial object which has been intentionally placed into
orbit. Such objects are sometimes called artificial satellites to
distinguish them from natural satellites such as the Moon.
4. NEED FOR HIGH ALTITUDE COMMUNICATION PLATFORM(HAP)
Wireless solutions are becoming increasingly important,
because wireless can offer high-bandwidth service
provision without reliance on fixed infrastructure and
represents a solution to the ‘last mile’ problem, i.e. delivery
directly to a customer’s premises, while in many scenarios
wireless may represent the only viable delivery mechanism.
5. LIMITATIONS OF SATELLITES AND TOWER
NETWORKING
Limited signal.
penetration through buildings.
High Cost.
Upgrading New Ones.
We Cannot Shift Capacities.
Network Building And Installation.
6. AERIAL COMMUNICATION PLATFORMS
A global communications network comprises a plurality of aerial
platforms or vehicles deployed at an altitude in or near the
stratosphere and permitted to drift in a controlled manner such that
each platform adjusts its position relative to other aerial platforms.
Each aerial platform has a propulsion system and control surfaces
and preferably includes a lighter-than-air component to maintain lift
in an economical manner.
7. BENEFITS OF HAPS OVER OTHER SYSTEMS
Closer to ground.
Dynamic to traffic demands.
Low Cost.
Deployed incrementally and rapidly.
Environment friendly.
using solar power.
Range upto 1-10 kms.
Speed 25-155 Mbps.
8. AIRSHIPS FOR HAPS
The past few years have seen a resurgence of interest in balloons and airships,
with technology developments such as new plastic envelope materials that are
strong, UV resistant and leak-proof to helium, which is now almost universally
used instead of the much cheaper hydrogen. Such hi-tech airships have
featured in high-profile attempts to circumnavigate the globe (for e.g. the
Breitling Orbiter10). Several high technology airship programs have been
launched recently for e.g. Zeppelin NT [8] and Cargo lifter in Germany.
Airships are thought to be the best alternative source of high altitude platforms
for communication
9. A study is being carried out regarding as a means of high altitude platforms for communication
A major business goal remains that of developing a stratospheric HAP capable of serving communication applications
economically and with a high degree of reliability. Whether an airship or an aeroplane, a major challenge is the
ability of the HAP to maintain station keeping in the face of winds
the wind profile with altitude may vary considerably with latitude and with season, a form similar to that shown in
Figure 1 will usually be obtained. This altitude (>16 km) is also above commercial air-traffic heights, which would
otherwise prove a potentially prohibitive constraint.
Figure 1. Typical Jet-Stream wind profile v/s altitude
10. BENEFITS OF AIRSHIPS AS HAPS
Continuous Communications and Surveillance
Coverage.
Upgrades.
Serves Multiple Applications.
Covering large region.
HAP Don’t require any launch vehicle.
Self Power generation using Solar.
HAP as Conventional Base Station.
Low Cost.
Environment Friendly.
Large Payload weight.
Portable.
11. PROBLEMS / CHALLENGES FACED BY AIRSHIP HAPS
Stratospheric environment and thermal condition.
Energy source for propulsion.
Energy storage.
Propulsive efficiency.
Aerodynamic design.
Ground handling.
Hull structure.
12. CURRENT DEVELOPMENT OF AIRSHIP HAP
The Wireless Innovation Systems Group of the Yokosuka Radio Communications Research
Center in Japan [7] (refer figure 3). The airship has a semi-rigid hull of ellipsoidal shape with
an overall length of nearly 200m. It is composed of an air-pressurized hull for maintaining a
fixed contour, 12 and internal bags filled with the buoyant helium gas. Two air ballonets are
installed inside the hull to keep the airship at a required attitude
13.
14. KEY FACTS ABOUT ATG STRATSAT PLATFORM
System capacity is 1000 billion call minutes a year.
A high-density focused coverage over a 7,000 sq. mile area .
The airship can hold position to within 0.5 km of its target
location.
The balloons will be covered with solar cells, giving energy to the
electrical motors.
The data rates foreseen for the fixed services are 2 Mbps for the
uplink and 10 Mbps for the downlink.
The data rates foreseen for the mobile services are 9.6 - 16 kbps
for voice and 384 kbps for data.
The cost of the entire project for a worldwide broadband
infrastructure is estimated at $2.5 billion .
15. CONCLUSION
Airships are low cost and travel from one place to place
by using Solar energy and Providing Network to every
place and saving the environment and providing high
speed network and portable .