Millimeter Wave Regulation IEEE EMC – DC/No. VA Mitchell Lazarus | January 31, 2012 Millimeter Wave Regulation IEEE EMC – DC/No. VA Mitchell Lazarus | January 31, 2012

Overview  FCC restricted bands  Communications  GHz (unlicensed)  GHz (unlicensed)  71-76, 81-86, GHz (licensed)  Radar – Current Rules  GHz  GHz  Radar – Waivers and Proposed Rules  GHz  GHz  GHz 1

Millimeter Wave Signals in General  Advantages  tight beams from small antennas  can reuse same frequency nearby  high data capacity  Disadvantages  need direct line-of-sight  high free space attenuation  high rain attenuation  poor penetration of walls and terrain. 2 At X GHz, a one-foot antenna has a diameter of X wavelengths.

FCC Restricted Bands  In the late 1980s, the FCC listed 64 “restricted bands”:  closed to unlicensed transmitters  range from 90 kHz to 36.5 GHz  to protect sensitive receivers: – GPS, radio astronomy, satellite downlinks, air traffic radars, etc.  FCC also declared all bands above 38.6 GHz to be “restricted”  Authorizing unlicensed use above 38.6 GHz always requires removal from the restricted list  part of the FCC rulemaking proceeding. 3

Communications 4

57-64 GHz (Unlicensed) – 1  Max average power 9 µW/cm² at 3 meters (40 dBm EIRP)  max peak 500 mW  Disadvantage: attenuation by O 2 molecules in atmosphere 5  WiGig Alliance:  in-room data communications  1-6 Gbits/sec  wireless HDMI, gaming, home storage network, etc.  proposed IEEE ad. Frequency (GHz) Source: Adelia C. Valdez Va Tech –64 GHz 16 8 dB/km 0

57-64 GHz (Unlicensed) – 2  Rulemaking proposal:  average power 82 dBm EIRP  minus 2 dB for every dB that antenna gain is below 51 dBi  antenna must be outdoors or pointed outdoors  Pending since June 2007  new rules possible in 2nd or 3rd quarter

92-95 GHz (Unlicensed)  Coextensive with GHz licensed band (next slide)  Max average power 9 µW/cm² at 3 meters (40 dBm EIRP)  max peak 500 mW  indoor only – minimizes interference to and from licensed users  No FCC certifications issued to date. 7

71-76, 81-86, GHz (Licensed)  Each applicant receives a non-exclusive, nationwide license  no limit on number issued  For each link:  electronic, real-time interference checks with Federal gov’t and non-gov’t incumbents  interference cases are rare (except on certain rooftops)  Max power 55 dBm EIRP  No licensed use on GHz  reserved for Federal research applications  Minimum bit rate:  71-76, 81-86: bits/sec/Hz  GHz: 1.0 bits/sec/Hz. 8

Radar (Current Rules) 9

57-64 GHz  GHz fixed field disturbance sensors:  max average power 9 µW/cm² at 3 meters (+40 dBm EIRP)  peak power density 18 µW/cm² at 3 meters (+43 dBm EIRP)  non-fixed or elsewhere in band:  max peak power density 9 nW/cm 2 at 3 meters (+10 dBm EIRP)  max peak transmitter output power 0.1 mW  Unlicensed. 10

76-77 GHz  Vehicle-mounted radars only  Unlicensed.  Power limits: 11 Forward-Looking (dBm EIRP) Side- or Rear- Looking (dBm EIRP) Vehicle moving Vehicle stopped+23.5

12 Radar (Waivers and Proposed Rules)

76-77 GHz (Proposed Rule)  100 watt (50 dBm) power limit  regardless of direction; moving or stopped  any application (not just vehicle-mounted)  Pending since May

76-77 GHz (Waiver)  Fixed use of 10 radars at Atlanta airport  for tracking aircraft and vehicles on ground  Must meet emissions limits for forward-looking, in-motion vehicle radars ( dBm EIRP)  Granted September

77-81 GHz (Proposed Rule & Waiver)  Use as in-tank level probing radars  limited to commercial use at fixed locations  Unlicensed  Proposed emissions limits:  +23 dBm EIRP average (measured with no tank wall)  +43 dBm EIRP peak (measured with no tank wall)  but pulse radars often have >20 dB P/A ratio  –41.3 dBm EIRP (§15.209) (measured through metal or concrete)  FCC acknowledges need to protect radio astronomy operations  Pending since January 2010  Waiver granted pending rulemaking  subject to above emissions limits. 15

78-81 GHz (Proposed Rule & Waiver)  Airport use to detect “foreign object debris” (FOD) on runways  aircraft parts, tools, equipment and supplies, rocks, pavement fragments, luggage, wildlife  FCC open to allowing other applications  No proposal as to licensed vs. unlicensed  No proposal as to power limits  FCC acknowledges need to protect radio astronomy operations  Pending since December 2011  Waiver granted pending rulemaking:  airport FOD detection only  35 dBW EIRP  license required. 16

Conclusion  Millimeter wave spectrum is the target of extensive engineering innovation  FCC rules at 57 GHz and above are badly out of date  FCC moving to update rules, but regulatory process is inherently slow. 17

18 Thank you! Mitchell Lazarus |