Slide 0 Spectrum on a Budget E DUCAUSE October 9, 2006 Mitchell Lazarus | |

Slide 1 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  GHz  GHz  GHz  TV white space  Hybrid licensing schemes.

Slide 2 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.

Slide 3 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).

Slide 4 FCC Licensing Regimes I.Exclusive license  e.g., BRS/EBS, others  most are now auctioned; some can be leased II.Frequency coordination  fixed microwave  spectrum is free; but entrant must protect incumbents III.Unlicensed operation  Wi-Fi, Bluethooth, many others  spectrum is free; but some bands are congested IV.Hybrid schemes  mostly in newly authorized bands  promising for reliable, low-cost implementations.

Slide 5 I. Exclusive License

Slide 6 EBS/BRS -- Background  Formerly 31 video channels at 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.

Slide 7 EBS/BRS – Evolution  “White space” around BRS licenses auctioned in  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.

Slide 8 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.

Slide 9 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.

Slide 10 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.

Slide 11 LMDS, 24 GHz, 39 GHz  All underused bands:  Local Multipoint Distribution Service (LMDS) , GHz (auctioned 1998)  24 GHz (auctioned 2004) , GHz  39 GHz (auctioned 2000) GHz  All have 10-year license terms  Renewal requires “substantial service”  licensees may be amenable to educational uses.

Slide 12 II. Frequency Coordination

Slide 13 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)  GHz  GHz  GHz (with gaps)  GHz.

Slide 14 III. Unlicensed Operation

Slide 15 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: 1.an unlicensed device must accept all interference 2.an unlicensed device may not cause harmful interference to a licensed user.

Slide 16 “Old” Unlicensed Bands  MHz  shared with licensed users  extremely congested  MHz  Wi-Fi “b” & “g”  shared with microwave ovens, cordless phones, etc.  moderately congested, getting worse fast  MHz  Wi-Fi “a”  rapidly becoming congested  Maximum power in all bands: 4+ watts  most applications use only a few hundredths of a watt.

Slide 17 “New” Unlicensed Bands  expanded 5 GHz  GHz  GHz  GHz  TV white space (pending).

Slide 18 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.

Slide 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.

Slide 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.

Slide GHz  Very clean spectrum  Very high data rates possible  Maximum power: 10 watts  But limited to indoor operation.  best regarded as experimental.

Slide 22 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.

Slide 23 IV. Hybrid Schemes

Slide 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.

Slide , 81-86, 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.

Slide 26 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.

Slide 27 Thank you! Mitchell Lazarus | |