A Wireless Tipping Point, Open Spectrum Implications

A Wireless Tipping Point, Open Spectrum Implications Brough Turner http://www.broughturner.com

1920s consumer radio receivers Philips 2501 Very early tech, i.e. primitive Crystal, Regenerative, Tuned RF … Poor selectivity, low sensitivity, low stability Tuned RF Crystal 2

Radio Spectrum Occupancy Urban areas, 30 MHz to 3 GHz. Above 3 GHz mostly vacant. As measured by Shared Spectrum Company and the University of Kansas Center for Research for the NSF National Radio Network Research Testbed (NRNRT) 3

New York City Unusually heavy communications during Republican National Convention August 30 to September 3, 2004 brought spectrum occupancy up to 13%. 4

Most spectrum idle most of the time 806 – 928 MHz Dublin Ireland Spectrum Occupancy Measurements Collected On April 16-18, 2007 Shared Spectrum Company, www.sharedspectrum.com 5

Open Spectrum Noise, Interference, Chaos … ! How could it work? 8

Open Spectrum Noise, Interference, Chaos … ! How could it work? Focus on Receiver Performance 9

Visible light analogy Our vision system (eyes + visual cortex) = extremely efficient 400-790 THz receiver The product of years of evolution! 10

Spatial discrimination For Humans: ~ 1/60th of a degree 11

Enormous knowledge base Detailed catalog of the characteristics of most potential visible light sources 12

Leveraging source motion to increase received information … 13

1920: Regulation made sense 14

1920: Regulation made sense 2009: We’ve come a long way 15

1920: Regulation made sense 2009: We’ve come a long way Shared use of unlicensed spectrum Enormous value creation 16

1920: Regulation made sense 2009: We’ve come a long way Shared use of unlicensed spectrum Enormous value creation Thermex Thermatron RF Dryers 17

Open spectrum prospects Regulation Vested interests TV White Spaces Crippled for now… 18

Open spectrum prospects Regulation Vested interests TV White Spaces Crippled for now… What about higher frequencies? 19

Spectrum Myth TV Spectrum is “beach front” spectrum 20

Spectrum Myth TV Spectrum is “beach front” spectrum Based on legacy technology, not physics! Travels farther – No! Goes thru walls – Not that different… 21

Refraction and reflections More at shorter wavelengths Multiple versions “Multipath” 22

MIMO: Multiple Input Multiple Output Multiple paths improve link reliability and increase spectral efficiency (bps per Hz), range and directionality 23

Rich Indoor MIMO Multipath Source: Fanny Mlinarsky, Octoscope 24

Municipal Multipath Environment Source: Fanny Mlinarsky, Octoscope 25

TVWS – Beach-front Property? MIMO antenna separation >= ½ wavelength 2.1 meters at 70 MHz 21 cm at 700 MHz But 2.5 cm for 5.8 GHz Wi-Fi D-Link DAP-2553 Wavion Networks 26

Multiple radios per chip Like CPU cores … Intel 2x2 MIMO – 2008 4x4 MIMO – 2010-11 then Fujitsu 8 radios, 16 radios?, … what to use the silicon for? Beam-forming ! AMD 27

Beamforming 2014: >200 Mbps Wi-Fi to >1 Km at mass market prices ? 4x4 MIMO with 12-16 antenna elements 28

Beamforming 2014: >200 Mbps Wi-Fi to >1 Km at mass market prices ? 4x4 MIMO with 12-16 antenna elements 29

Gaining spectrum for open use Seeking only “Secondary access” No interference with existing users Geographic database; Listen-before-talk License-exempt stations under positive control of a “lightly” licensed station 30

Wi-Fi 802.11y - 2008 Rich protocol set for “secondary access” 31

Open spectrum Wireless tipping point ahead Focus on spectrum blocks above 3 GHz More access at 5 GHz (4.9-6 GHz) Anything between 6-10 GHz “Secondary use” Light licensing – 802.11y protocols 32

Thank You Brough Turner broughturner@gmail.com rbt@ashtonbrooke.com

Credits Beyond those noted on individual pages… Images… Office building facade: http://commons.wikimedia.org/wiki/User:Beek100 Laptop icon: http://www.flickr.com/photos/ichibod/ Microwave oven: http://www.flickr.com/photos/code_martial/ 802.11n performance in the field http://www.tomshardware.com/reviews/beamforming-wifi-ruckus,2390.html http://www.muniwireless.com/2009/02/23/80211n-dramatically-improves- outdoor-wifi/ 34

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A Wireless Tipping Point, Open Spectrum Implications

by Brough Turner on Oct 28, 2009

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A Wireless Tipping Point, Open Spectrum Implications — Presentation Transcript