0 Slide 0 Evolving Methods of Controlling Interference National Spectrum Managers Association May 19, 2004 Mitchell Lazarus | |

1 Slide 1 Traditional FCC Categories  Broadcast  Geographic licensed  Site licensed  frequency coordinated as a prerequisite to licensing  e.g., point-to-point microwave, private land mobile  Unlicensed  only frequency and power are regulated  no other interference prevention  Other  e.g., Citizens Band, GMRS, etc.

2 Slide 2 Emerging FCC Regulation  Most new spectrum is allocated for:  unlicensed use with requirements for interference protection, or  licensed but not traditionally coordinated. ... intermediate between traditional frequency coordination and traditional unlicensed.

3 Slide 3 Examples in the Past Year  71-76, 81-86, GHz  Dedicated short-range communications service  4.9 GHz public safety  Expanded 5 GHz U-NII band  Interference temperature (proposed)  Unlicensed operation at MHz (proposed)  Unlicensed operation in vacant TV bands (proposed). Each of these falls somewhere between conventionally frequency coordinated and free-for-all unlicensed.

4 Slide , 81-86, GHz  Licensed.  Every licensee receives nationwide authority on all bands.  Licensees register links with a third-party database.  If harmful interference occurs, the later-registered link must modify or discontinue use.  Licensees must also coordinate with the federal government via a separate database.

5 Slide 5 DSRC at 5.9 GHz  Licensed.  Every licensee receives non-exclusive authority for the entire band over a specified geographic area:  governmental entities by jurisdiction  others by county, state, multi-state, or nationwide  All users share a dedicated control channel that prioritizes among transmissions and avoids conflicts.

6 Slide GHz Public Safety  Licensed by geographic safety agency’s area of jurisdiction.  All licensees share all frequencies.  Regional Planning Committees set up coordination procedures.  plans must incorporate flexibility for dynamic spectrum utilization in response to emergencies.  Coordination is not a prerequisite to licensing.

7 Slide 7 Expanded 5 GHz U-NII Band  Unlicensed.  Must protect federal installations.  All systems must employ dynamic frequency selection.  protects only radars, not other U-NII devices  All devices must employ transmit power control  should help to increase the useful density of U-NII devices.

8 Slide 8 Interference temperature (proposed)  Unlicensed.  Elaborate monitoring scheme keep unlicensed devices below the interference threshold of licensed receivers.  relies on real-time assessment of RF environment.

9 Slide 9 Unlicensed at MHz (proposed)  Unlicensed.  Must protect 103 earth stations and three federal radars.  Proposals (fixed): rely on database of incumbents.  Proposals (non-fixed):  devices monitor earth station uplink frequencies, or  each earth station transmits a beacon that controls nearby unlicensed devices.

10 Slide 10 Unlicensed in Vacant TV Bands (proposed)  Unlicensed.  Must protect usable TV signals in the area.  Details of FCC proposals are not yet available (NPRM not released).  NOI proposed:  dynamic frequency selection  GPS and database lookup.

11 Slide 11 Trends  Shift from traditional coordination to  “Frequency coordination on the fly” uses on-board technology (e.g., DFS, APC, DSRC control channel)  reliance on databases

12 Slide 12 Emerging Needs  Development of criteria for on-board interference prevention.  i.e., specifying conditions under which a channel can safely be used without causing interference to others  Development and maintenance of databases for interference prevention. e.g.:  71-76, 81-86, GHz  Broadband over power line  The FCC has overlooked the difficulty of these tasks.  NSMA is a unique repository of needed expertise.

13 Slide 13 Thank you! Mitchell Lazarus | |