Post on 18-Dec-2015
Alternative Internet Access Technologies
Prof. R. Struzakryszard.struzak@bluewin.ch
School on Radio Use for Information and Communication TechnologyThe Abdus Salam International Centre for Theoretical Physics ICTP Trieste (Italy) 3 - 21 February 2003
These are preliminary notes, intended only for distribution to participants
Topics for discussion
Current research activities in various countries aimed at making internet access less expensive and/or more practical: – PLT – HAP
– Beware of misprints!!!
Existing Technologies
Strengths Weaknesses
Fiber Large bandwidth Capital/ Labor intensive
Cable Popular in many rich countries Capital/ Labor intensive
xDSL Popular in cities/ rich countries Distance limits availability
Radio Rapid deployment Coverage problems
Satellite Ubiquitous coverage Capital intensive
Most have lengthy/ costly deployment process, especially new installations
Power Line Telecommunication
• Electric power transmission network much more developed than telecommunication network
• New high-power, high-voltage power lines integrated with fiber optic cable
• Low-power line exist in most houses
PLC References• Bartak GF, Powerline Communication Systems…,IEEE Internat.
EMC 2003 Sympos., Istanbul• Olsen RG, Technical Considerations for Wideband Powerline
Communication, IEEE Internat. EMC 2003 Sympos., Istanbul• Vick D, PLC Workshop, Internat. Wroclaw EMC 2000 Sympos. (first
findings & simulations)• Hansen D, Update on Power Line Telecommunication Activities in
Europe, IEEE Internat. EMC 2003 Sympos., Istanbul• www.PLCforum.com• www.plca.net • www.ipcf.org• www.ascom.ch• www.broadband.ch
PLC Forum PresentationBucharest 2002
HAP
HAP – High Altitude Platforms
• High Altitude Platform Stations technology is a way to keep antenna at high altitude (stratospheric heights of ~20 km) at low cost
• It has a potential of high capacity & coverage: a single platform has >1000 X capacity of satellite (in bps/km2)
• The stations are rapidly deployable (system set up in days, providing instant market coverage)
• Relatively inexpensive: the cost of the complete system is expected to be a fraction of the cost of satellites & terrestrial systems such as cable, DSL, or fiber to deploy ($/subscriber)
• Easy maintenance: Platforms brought down at will for maintenance/ upgrade
• Easily re-locatable
• Complement to terrestrial & satellite systems• Low power (~1W –compare with 10kW for typical terrestrial broadcast)
• Multiple applications– Fixed/mobile broadband– Fixed/mobile voice– Direct broadcating video/audio– Non-telecom applications
• (e.g. environmental observations)
HAPS’ Footprint
• For a given altitude, the diameter of HAPS’ footprint is
• For elevation of 150, the footprint is of ~150 km diameter, for 00 - ~1000 km diameter.
2 arccos cos_
Earth radius (6'378 km)
the minimum elevation angle
altitude
Rd R
R h
R
h
HELIOS Flying
HAP References• Many publications & ITU documents• HAPS-High Altitude Platform Stations, Federal Office of
Communications, Switzerland• http://skystation.com (presentation)• www.angelhalo.com• www.airship.com • www.plfm.net • www.ga.com/avcs/index.html• http:/www1.tlc.polito.it/heliplat • www2.crl.go.jp/team2/ • www2.crl.go.jp/mt/b181/research/spf/index-e.html (presentation)• http://skytowerglobal.com• www.bacom.ch/imperia/md/content/english/funk/forshungundentwicklung/studien/HA
PS.pdf
•
Japanese Presentation
Thank you for your attention