802.11 WNG Presentation on the use of UWB spectrum for 802.11 July 2007 Nov 2009 March 2011 802.11 WNG Presentation on the use of UWB spectrum for 802.11 Date: 2011-03-15 Authors: Peter Ecclesine (Cisco Systems)

Nov 2009 March 2011 Abstract This document presents the possibility of using existing shared spectrum allocation for ultrawideband as a new frequency band for 802.11ac MAC and PHY with a 500MHz bandwidth.

March 2011 UWB Background The US FCC announced spectrum availability of 3-10.5GHz for UWB in February, 2002 “Spectral underlay” – operates without any spectrum etiquette or spectrum sensing PSD limit: -41.3dBm/MHz ≈ -14dBm in a 500MHz BW 500MHz (or 20% fractional bandwidth) minimum Most other countries have now finalized UWB regulations UK, EU, Korea, China, Canada, Japan Operation from 5-6GHz generally not allowed Many restrictions in 3-5GHz, including spectrum sensing (DAA) Operation above 8.5GHz either not allowed or requires DFS Some IEEE efforts have addressed this spectrum 802.15.3a – withdrew PAR in January 2006 802.15.4a – Approved in March 2007, but minimal market deployment UWB spectrum is underutilized and globally available

Worldwide Regulations for UWB Nov 2009 March 2011 Worldwide Regulations for UWB Globally Available US Feb-02 EU Dec-06 2010 w/DAA 2010 w/DAA See Note 2010 w/DAA Japan Sep-2006 2010 w/DAA 2010 w/DAA Korea Sep-2006 2010 w/DAA 2010 w/DAA 2010 w/DAA Canada March-2009 China Jan-09 2010 w/DAA 3.168 GHz 4.752 6.336 7.392 7.920 8.976 9.504 10.560 Over 1GHz of contiguous bandwidth from 7.25-8.5GHz is available globally without restriction Minimum bandwidth is 450 or 500MHz Peter Ecclesine (Cisco Systems)

Why UWB for 802.11? Adds needed capacity for high rate communications March 2011 Why UWB for 802.11? Adds needed capacity for high rate communications Wireless docking/monitors using 802.11ac will tax existing 5GHz spectrum allocation Some countries highly restrict 5GHz spectrum (China) High density environments (cubicle farms) will have serious spatial capacity problems Could leverage existing 802.11ac MAC and PHY extensions MU-MIMO, STBC, and other extensions will greatly enhance link budget…more than doubling range High bandwidth allows precision ranging/location For applications that need relatively short range (<10 meters) and very high spatial capacity, this spectrum could be ideal

Cube farm spatial capacity March 2011 Cube farm spatial capacity 2.5 m At 320Mb/s at 8.2GHz, radius of coverage is ~2 meters with SISO OFDM In a 10x10 foot space, this provides an aggregate spatial capacity of 5.12Gb/s Minimum of 4 channels is required Could be shared band On a per square meter basis, this is 512Mb/s/m2 Negligible interference between users Small cells yield highest spatial capacity in users per square meter SISO OFDM UWB has a coverage area just larger than an average cubicle Channel reuse can optimize capacity with minimum interference

March 2011 What would be involved? Existing 802.11ac PHY + MAC provides most of the hooks 450/500MHz minimum bandwidth will require new MCS combinations Beamforming may not be useful MIMO/MU-MIMO could be very useful Can use simpler OFDM modulation Shannon capacity of 500MHz channel is very high at low SNR At least two 500MHz channels are available in 7.25-8.5GHz Studies may be required to see how well MU-MIMO will operate Other regulatory domains may permit <500MHz BW

Next steps Solicitation for additional WNG presentations March 2011 Next steps Solicitation for additional WNG presentations Comments/discussion? Straw poll: Should further work be done on this topic? Y: 33 N: 0 d/c: 5 Should we approach 802.11ac this week to request feedback from them? Y: 26 N: 0 d/c: 7