Advantages over satellite and terrestrial networks
Power system and system requirements
3. What is HALO ?
The High Altitude Long Operation Network TMis a broadband wireless metropolitan area network, with a star topology.
High Altitude Aeronautical Platform Station (HAAPS) is the technology used here.
The HALO network will be located in the atmosphere, at an altitude miles above terrestrial wireless, but hundreds to thousands of miles below satellite networks.
HAAPS means a solar powered unmanned airship capable of long endurance-may be of several years.
4. System architecture
HALO Aircrafts contains network elements including an ATM switch, spot beam antennas, and multibeam antennas, as well as transmitting and receiving electronics.
The antenna array provides cellular-like coverage of a large metropolitan area.
The HALO network can be connected to non-HALO networks, such as ATM networks, Internet, and frame relay via an HG/interworking unit (IWU).
5. 6. Types of HAAPS
Lighter than air HAAPS are kept stationary. They are probably air balloons floating in air.
Other type is Airplane based HAAPS which are flown in a tight circle.
For broadcast application a simple antenna beams signals to terminals on the ground.
7. 8. HALO Network concepts
HALO Aircraft present a new layer in the hierarchy of wireless communication - a 10 mile tall tower in stratosphere.
It is in a level above rain shower and below meteor shower.
HALO Network plane is the central node of the broad band communication.
The capacity is in the range of 10-100 Gb/s.
9. 10. Elements of HALO Network
A MMW antenna array and its related components will be located in a pod suspended below air craft fuselage.
Antenna array will produce many beams typically more than 100.
Each beams will be separated by a fixed frequency.
Over satellite network
Satellite network have expensive high power user terminal and long propagation delay.
system capacity is practically fixed.
Establishinga new satellite is very expensive.
Over Terrestrial network
Terrestrial networks have low look angles and complex infrastructure.
They require many base stations that must be interlinked with cables.
13. Power system and system requirements
Aircrafts power system consist of photovoltaic cell and a regenerative fuel cell.
Advantage of using this is that it eliminates the need of and compress air at high altitude.
Aircraft size increases with increasing altitude.
14. Aero plane properties
The HALO aircraftswill be operated in shifts from regional airport.
HALO aero plane is specially designed forcarry the hub devices and they are having long lifetime.
Look angle will be greater than 20 degree.
So the network will available in a super metropolitan area(includingurban, suburban and surrounding rural area).
15. Other properties
HALO network can interface with the local LAN connections.
It can Interface between broadband protocols like ATM and SONET.
The HALO network will provide access to the PSTN and become the backbone for internet services like world wide web.
16. Subscribers Network relation 17. Desirable Features
Seamless multimedia services.
Adaptation to end user environment.
Rapidly deployable to sites of opportunity.
Bandwidth on demand for efficient use of available spectrum .
Widely separated customers can receive same communication asi n entertainment broadcasting.
We can accessinteractive TV and internet.
Costumers can have large coverage area in telecommunicationcompared to terrestrial network.
Can use as a communication techniques for remote areas.
Can use in marine communication system.
19. HALO Network coverage 20. References
J. Martin and N. Colella, "Broadband Wireless Services from High Altitude Long Operation (HALO) Aircraft,"Proc. of the SPIE International Symposium on Voice, Video, and Data Communications: Broadband Engineering for Multimedia Markets , 2000 .
G. Djuknic, J. Freidenfelds, et al., "Establishing Wireless Communications Services via High-Altitude Aeronautical Platforms: A Concept Whose Time Has Come?"IEEE Communications Magazine , September 2000.