‘unlocking the band’ ‘unlocking the 28ghz band’ matt hobby – system engineer
TRANSCRIPT
‘‘Unlocking the Unlocking the 28GHz Band’ Band’
Matt Hobby – System Engineer
The Last Mile
Last Mile
City - UrbanSuburban
RuralLocal Loop
End User Point of Presence
Existing Technologies
ADSL + Low Cost - Future Proof
Satellite + Nationwide Coverage
-Latency-Cost/ Contention
Leased Line + Speed - Rollout Cost
LIBRA
LIBRA
• Low-cost Internet Broadband Radio– Licensed 28 GHz spectrum– 40 km radius super-cell– Uses conventional BFWA equipment– 15,000 uncontended symmetric
connections– Places a 30m mast within 1 km of every
subscriber
Satellites, HAPs, LAPs & TowersSatellite @ 300+ km
HAP @ 21 km
LAP @ 1.5 km
Tower @ 0.3 km
Like a HAP but . . . . . .
• Based on existing technology
• Station keeping guaranteed by tether
• Power requirements guaranteed
• Spectrally efficient backhaul via tether
• Low cost!
Equivalent Tower Model
Aerostat
CPE
Free Spaceregion
30 m mast
Shadowing & LOS
80%+ LOS @ 40 km
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Pro
babili
ty
Range (km)
Probability of LOS path
The Link Budget
• Extremely High Gain BS antenna
• QPSK modulation
• Standard 60 cm CPE dish @ boundary
• 99.9% availability
• Rain band F assumed
Technology
Trials
Target Cost to End User
• > 2 Mbit/s
• Uncontended
• Symmetric
• ~ £300 per link to Network Operator
• End User cost of ~ £350
Roadmap
Integratepayload
Commercialdemonstrator
Full systemdeployment
April 2003 January 2004 January 2005
ConclusionLIBRA
The LONG TERM solution for Broadband Britain !
Aerostat Advantage @ 1 km