280 likes | 383 Views
Spectrum on a Budget E DUCAUSE October 9, 2006 Mitchell Lazarus | 703-812-0440 | lazarus@fhhlaw.com. Overview. Criteria for evaluating spectrum FCC licensing regimes Educational Broadband Service (formerly ITFS) LMDS, 24 GHz, 39 GHz Fixed service New unlicensed bands expanded 5 GHz
E N D
Spectrum on a BudgetEDUCAUSEOctober 9, 2006Mitchell Lazarus | 703-812-0440 | lazarus@fhhlaw.com
Overview • Criteria for evaluating spectrum • FCC licensing regimes • Educational Broadband Service (formerly ITFS) • LMDS, 24 GHz, 39 GHz • Fixed service • New unlicensed bands • expanded 5 GHz • 24-24.25 GHz • 57-64 GHz • 92-95 GHz • TV white space • Hybrid licensing schemes.
Introduction • Spectrum is the new real estate • essential for commerce and education • fixed supply – i.e., “they’re not making any more of it” • location (frequency) is everything • Well-established locations are crowded and expensive • bargains are still available in less developed areas.
Criteria for Evaluating Spectrum • End-user compatibility • (consumer end use: Wi-Fi) • Frequency range • low: better propagation and building penetration • high: better directionality, smaller antennas • Degree of congestion (reduces reliability and throughput) • Cost of spectrum • auction / lease / “free” license / unlicensed • Cost (and availability) of equipment • worse for higher frequencies, newly authorized bands • FCC rules (power limits, service restrictions).
FCC Licensing Regimes • Exclusive license • e.g., BRS/EBS, others • most are now auctioned; some can be leased • Frequency coordination • fixed microwave • spectrum is free; but entrant must protect incumbents • Unlicensed operation • Wi-Fi, Bluethooth, many others • spectrum is free; but some bands are congested • Hybrid schemes • mostly in newly authorized bands • promising for reliable, low-cost implementations.
EBS/BRS -- Background • Formerly 31 video channels at 2500-2690 MHz • Educational Broadband Service (EBS) • formerly Instructional Television Fixed Service (ITFS), established in 1963 • used to distribute educational programming • Broadband Radio Service (BRS) • formerly Multichannel Multipoint Distribution Service (MMDS), established in 1983 • used for “wireless cable” entertainment services • MMDS often leased additional capacity from ITFS • and often paid for ITFS facilities.
EBS/BRS – Evolution • “White space” around BRS licenses auctioned in 1995-96 • Sprint now holds a majority of BRS area licenses • (EBS white space still open) • Transition from video delivery to two-way broadband: • 1996: data delivery • 1998: two-way digital operation • 2001: mobile service • 2004: EBS and BRS frequencies repackaged • 2006: rules for transition to new frequency plan.
Repackaged EBS • Three band segments: • upper and lower, each: 12 5.5 MHz, 1 6 MHz, 1 4 GHz • middle: 7 6 MHz (suitable for current video service) • ITFS now holding four 6 MHz channels will receive: • one 6 MHz in middle band • three 5.5 MHz in lower or upper band • one 1 MHz in a 4 MH band • ITFS now holding one 6 MHz channel will receive: • one 6 MHz in middle or one 5.5 MHz in lower or upper.
Changing EBS Operation • Incumbents are protected against interference • Conversion to new frequencies will be fully funded • BRS licensees will negotiate transition • Leasing of EBS spectrum is allowed • licensees must reserve 5% for their own use • licensees have certain rights to recapture spectrum.
EBS – Coming Developments • FCC plans to auction “white space” around EBS licenses • Only EBS eligibles may participate • but EBS bidders can accept funding from commercial interests, then lease out spectrum • Auction not yet scheduled • will be offered by geographic areas • may be separate channels or all channels together.
LMDS, 24 GHz, 39 GHz • All underused bands: • Local Multipoint Distribution Service (LMDS) • 27.5- 29.25, 31-31.3 GHz (auctioned 1998) • 24 GHz (auctioned 2004) • 24.25-24.45, 25.05-25.25 GHz • 39 GHz (auctioned 2000) • 38.6 - 40.0 GHz • All have 10-year license terms • Renewal requires “substantial service” • licensees may be amenable to educational uses.
Fixed Service • Suitable for long-distance, high-speed communication among fixed points • Equipment is readily available • Spectrum is free • but requires frequency coordination and license • not free -- $1-2.5K per link • newcomers must fit in among existing users • Bands (partial listing) • 10.55-10.68 GHz • 10.7-11.7 GHz • 17.7-19.7 GHz (with gaps) • 21.2-23.6 GHz.
Unlicensed Operation -- Principles • FCC sets technical rules (power, etc.) • intended to minimize interference to other users • Device is FCC certified as complying with technical rules • must be labeled with “FCC ID” number • Anyone may operate a certified device anywhere in U.S. • Interference rules: • an unlicensed device must accept all interference • an unlicensed device may not cause harmful interference to a licensed user.
“Old” Unlicensed Bands • 902-928 MHz • shared with licensed users • extremely congested • 2400-2483.5 MHz • Wi-Fi “b” & “g” • shared with microwave ovens, cordless phones, etc. • moderately congested, getting worse fast • 5725-5850 MHz • Wi-Fi “a” • rapidly becoming congested • Maximum power in all bands: 4+ watts • most applications use only a few hundredths of a watt.
“New” Unlicensed Bands • expanded 5 GHz • 24-24.25 GHz • 57-64 GHz • 92-95 GHz • TV white space (pending).
Expanded 5 GHz • FCC added 255 MHz to 5 GHz band • tripled the band • “Dynamic frequency selection” (DFS) required to protect federal radars • devices must monitor for radars, change frequency • “Transmit power control” (TPC) required • automatically reduces output power to minimum needed • Should eventually take pressure off Wi-Fi b & g.
24-24.25 GHz • Lightly used • Maximum power for area coverage: 1/5o watt • comparable to most Wi-Fi • Point-to-point operation • maximum power: 1.9 watts • only in upper 80% of band • suitable for multiple T-1 speeds over hundreds of meters.
57-64 GHz • Lightly used band; mature technology • Provides extremely high data rates • can reach multiple gigabits/second • Tight antenna focus • hinders eavesdropping; improves security • Maximum power: 10 watts • Factors limiting range: • absorption by atmospheric oxygen • high rain fade.
92-95 GHz • Very clean spectrum • Very high data rates possible • Maximum power: 10 watts • But limited to indoor operation. • best regarded as experimental.
TV White Space (Proposed) • FCC considering unlicensed use of vacant TV channels • proposes fixed and mobile applications • broadcasters oppose • IEEE (standards group) recommends fixed use only • e.g., for local broadband distribution • IEEE-proposed interference protection: • base station programmed for locally vacant channels • remote stations operate only under control of base • all remotes monitor for TV signals and report to base • FCC announcement expected October 12.
3650-3700 MHz • Every license allows nationwide use of the entire band • fixed and base stations are entered in an FCC database • new stations must protect incumbents • mobile stations require a control signal from a fixed or base station • Radios must use spectrum-sharing protocols • Licensees resolve interference issues among themselves • Band is under-used • commercial interests are wary of non-exclusive spectrum.
71-76, 81-86, 92-95 GHz • Every license allows nationwide use of any bandwidth • can be used only for point-to-point communication • Licensees register links in an automated database • new links must protect earlier-registered links • If harmful interference occurs, the later-registered link must resolve it • assumption: beams are narrow and will rarely interfere.
Conclusion • Safe, established spectrum options are usually the most expensive • The FCC and manufacturers are working to open new bands • A willingness to innovate is the best route to reliable communications at low cost.
Thank you! Mitchell Lazarus | 703-812-0440 | lazarus@fhhlaw.com