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7/28/2019 22-10-0073-03-0000-802-22-overview-and-core-technologies
1/16
doc.: IEEE 802.22-10/0073r03
Submission
June 2010
Apurva N. Mody, BAE SystemsSlide 1
IEEE 802.22 Wireless Regional Area NetworksEnabling Rural Broadband Wireless Access Using Cognitive Radio Technology
IEEE P802.22 Wireless RANs Date: 2010-06-15
Name Company Address Phone email
Apurva N. Mody BAE Systems P. O. Box 868,
MER 15-2350,Nashua, NH 03061
1-404-819-
0314, 1-603-885-2621
apurva.mody@baesyst
ems.com,
apurva_mody@yahoo.
com
Gerald
Chouinard
Communication
s Research
Center, Canada
1-613-998-
2500
Gerald.chouinard@crc
.ca
Authors:
Notice: This document has been prepared to assist IEEE 802.22. It is offered as a basis for d iscussion and is not bind ing on the cont ributing individual(s) or organization(s). The material inthis document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.
Release: The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEEStandards publication; to copyright in the IEEEs name any IEEE Standards publication even though it may include portions ofthis contribution; and at the IEEEs sole discretion to permit
others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802.22 .
Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures http://standards.ieee.org/guides/bylaws/sb-bylaws.pdf including thestatement "IEEE standards may include the known use of patent(s), including patent applicat ions, provided the IEEE receives assurance from the patent holder or applicant with respect to
patents essential for compliance with both mandatory and optional portions of the standard." Early disclosure to the Working Group of patent information that might be relevant to the standard
is essential to reduce the possibility for delays in the development process and increase the likelihood that the draft publi cation will be approved for publication. Please notify the Chair
Apurva N. Mody < [email protected] > as early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a
draft standard being developed within the IEEE 802.22 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at [email protected].
>
http://standards.ieee.org/guides/bylaws/sb-bylaws.pdfhttp://standards.ieee.org/guides/bylaws/sb-bylaws.pdfmailto:[email protected]://standards.ieee.org/guides/bylaws/sb-bylaws.pdfmailto:[email protected]:[email protected]:[email protected]:[email protected]://standards.ieee.org/guides/bylaws/sb-bylaws.pdfhttp://standards.ieee.org/guides/bylaws/sb-bylaws.pdfhttp://standards.ieee.org/guides/bylaws/sb-bylaws.pdf7/28/2019 22-10-0073-03-0000-802-22-overview-and-core-technologies
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Submission
IEEE 802.22 Standard Overview IEEE Standards and IEEE 802.22
Overview of the IEEE 802.22
CONOPS
Reference Architecture
Frame Structure PHY
MAC
Cognitive Radio Capabilities
Spectrum Sensing
Geo-location
Interface to Incumbent Database Service
Security
Outline
June 2010
Apurva N. Mody, BAE SystemsSlide 2
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Slide 3
802.22
WRAN
Courtesy, Paul Nikolich, Chair,
IEEE 802
IEEE Standards Association Hierarchy
June 2010
802.15
WPAN
802.11
WLAN
More than 300
Standards Being
Developed Under
the IEEE SA
Umbrella
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Overview of the IEEE 802.22 Standard Focus - Rural Broadband Wireless Access
Core Technology - Cognitive radio technology based
un-licensed use, primarily designed to operate in the
TV Whitespaces from 54-862 MHz, on a non-
interfering basis with the primary users (incumbents).
RepresentationCommercial industry, Broadcasters,
Govt., regulators, and Academia
Membership40 on an average
ProjectsIEEE 802.22, IEEE 802.22.1, IEEE
802.22.1
CONOPS - VHF and UHF band operation allows long
range propagation and cell radius of 1733 km.
Approx 280 MHz of Bandwidth with 47 TV channels.
PHY - Optimized for long channel response times and
highly frequency selective fading channels.
MACProvides compensation for long round trip
delays
Unique features introduced for Cognitive Radio based
operation: spectrum sensing, spectrum management,
intra-system co-existence, geo-location and security
Mobility and Portability - PortabilityIEEE 802.22allows portability (nomadic use). In case the rules dochange, IEEE 802.22 PHY is designed to support mobilityof up to 114 km/hr (no hand-off is included in the currentversion).
PHY optimized to
tolerate long channel
response and
frequency selective
fading channel
MAC providescompensation for
long round trip
delays
June 2010
Apurva N. Mody, BAE SystemsSlide 4
Cognitive radio based un-
licensed usage, ideally
suited for regional and
rural broadband wirelessaccess
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IEEE 802.22 CONOPS
Operation in the VHF / UHF Bands. Frequency Allocation for the
United States5460, 7688, 174216, 470 - 608 and 614
698 MHz => Total of 282 MHz or 47 Channels
Network TopologyPoint-to-Multipoint (PMP)
Max EIRP and Cell RadiusFixed BS and Fixed Subscribers
using 4W EIRP, Cell Radius 10 100 km. Portable Subscribers
Station Supported. (Higher power BS allowed in other countries)
Tx / Rx antennaBS uses sectorized or omni-directional antenna.
At the subscriber Tx /Rx antenna is directional with 14 dB of front-
to-back lobe suppression,
Sensing antenna - Requires horizontal and vertical polarization
sensitivities to sense TV and microphone signals respectively, with
omni-directional pattern.
Geo-location - GPS based geo-location is mandatory, but terrestrial
geo-location (triangulation) is supported.
Sensing and GPS
Antennas
Directional Tx / Rx
Antenna at the
Subscriber
June 2010
Apurva N. Mody, BAE SystemsSlide 5
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Submission Slide 6
The proposed Protocol
Reference Model (PRM)
separates the Cognitive Plane
from the Data, Control and
Management planes
IEEE 802.22Cognitive Node: Reference
Architecture
June 2010
Apurva N. Mody, BAE Systems
IEEE 802.22 Provides Three
Mechanisms for Incumbent
Protection
Sensing
Database Access
Specially Designed Beacon
One or more protection
mechanisms can be adopted
based on the regulatory domain
requirements.
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IEEE 802.22Frame Structure 802.22 supports Time DivisionDuplex (TDD) frame structure
Super-frame: 160 ms, Frame: 10 ms
Each frame consists ofdownlink(DL) sub-frame, uplink (UL) sub-
frame, and the Co-existence Beacon
Protocol (CBP) burst
Lengths of DL and UL sub-frames
can be adjusted .
Self Co-existence Window: BS
commands subscribers to send out
CBPs for 802.22
self co-existenceCBP bursts
contain information about the backup
channel sets and sensing times
terrestrial geo-location and
whitespace device identification asrequired by the regulatory domain
rules.
Co-existence Beacon Protocol (CBP) burst
used for 802.22 self co-existence and
terrestrial geo-location A BCBP
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IEEE 802.22PHY Features
PHY capacity Mbit/s bit/(s*Hz) PHY performance: SNR (dB)
Mod. Rate CP= 1/8 Mod. Rate SNR
QPSK
1/2 3.74 0.624
QPSK
1/2 4.3
2/3 4.99 0.832 2/3 6.1
3/4 5.62 0.936 3/4 7.1
5/6 6.24 1.04 5/6 8.1
16QAM
1/2 7.49 1.248
16QAM
1/2 10.2
2/3 9.98 1.664 2/3 12.4
3/4 11.23 1.872 3/4 13.5
5/6 12.48 2.08 5/6 14.8
64QAM
1/2 11.23 1.872
64QAM
1/2 15.6
2/3 14.98 2.496 2/3 18.3
3/4 16.85 2.808 3/4 19.7
5/6 18.72 3.12 5/6 20.9Note: includes phase noise: -80dBc/Hz at
1 kHz and 10 kHz and -105 dBc/Hz at
100 kHz
PHY Transport - 802.22 uses Orthogonal Frequency Division
Multiplexing (OFDM) as transport mechanism. Orthogonal Frequency
Division Multiple Access (OFDMA) is used in the UL
Modulation - QPSK, 16-QAM and 64-QAM supported
CodingConvolutional Code is Mandatory. Turbo, LDPC or Shortened
Block Turbo Code are Optional but recommended.
Pilot Pattern - Each OFDM / OFDMA symbol is divided into sub-
channels of 28 sub-carriers of which 4 are pilots. Pilot symbols are
inserted once every 7 sub-carriers. Pilots cycle through all 7 sub-carriers
over 7 symbol duration. No frequency domain interpolation is required.
Net Spectral Efficiency - 0.624 bits/s/Hz3.12 bits/s/Hz
Spectral Mask- 802.22 has adopted the Spectral Mask requirements
proposed by FCC. (200 tap FIR filter may be needed for implementation).
June 2010
Apurva N. Mody, BAE SystemsSlide 8
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IEEE 802.22MAC Features
frame 0
Superframe n-1 Superframe n Superframe n+1
. . .
160 ms
frame 1
10 ms
frame 15
...Time...
10 ms 10 ms
Quiet Period Quiet Period
frame 0
Superframe n-1 Superframe n+1
. . .
160 ms
frame 1
10 ms
frame 15
...Time...
10 ms 10 ms
Quiet Period
Quiet Period
Connection-oriented MAC, establishes connection IDs and service flows which are dynamically created
QoSVarious types of QoS services are supported (See below). ARQ supported. Uni-cast, Multi-cast and broadcast
services are supported.
Cognitive functionality
Dynamic and adaptive scheduling of quiet periods to allow the system to balance QoS requirements of users with
the need to quiet down the network to support spectrum sensing. Quiet periods range from 1 symbol (approx. 1/3
ms) to one super-frame
Subscribers can alert the BS, the presence of incumbents in a number of ways. Dedicated - Urgent Co-existence
Situation (UCS) messages or low priority MAC messages
BS can ask one or more subscribers to move to another channel in a number of ways usingFrame Control Header (FCH)
or dedicated MAC messages
Intra-frame quiet period scheduling
Inter frame quiet period scheduling
QoS Application
UGS VoIP, T1 / E1
rtPS MPEG video
streaming
nrtPS FTP
BE E-mail
Contention BW request etc.
June 2010
Apurva N. Mody, BAE SystemsSlide 9
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IEEE 802.22Cognitive Radio Capability
Spectrum Manager
Policies
Incumbent Database
Service
IncumbentDatabase
Spectrum SensingRF sensing performance
0.1%
1.0%
10.0%
100.0%
-26 -24 -22 -20 -18 -16 -14 -12 -10 -8 -6 -4 -2
SNR(dB)
Probabilityofmisdetection(Pmd)
Energy-1dB Pfa=10% 5 ms
Energy-0.5dB Pfa=10% 5 ms
Energy-0dB Pfa=10% 5ms
Thomson-SegmentPfa=10% 4 ms
I2R Pfa=0.1% 4ms
I2R Pfa= 1% 4ms
I2R Pfa=10% 4 ms
Qualcomm Field Pfa=10% 24 ms
Qualcom Field Pfa=1% 24 ms
Thomson Field Pfa=10% 24 ms
Thomson Field Pfa=1% 24ms
Channel Set Management Subscriber Registration
and Tracking
Self Co-existence
time
C el l1 Ce ll 2 C el l3 C el l3 Ce ll 1 C el l2 Ce ll 1 C el l1 Ce ll 2 C el l3
Super-frame N (16 Frames) Super-frame N+1 (16 Frames)
CoexistenceBeaconWindowsDataFrames
TV ChannelX
Geo-location
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IEEE 802.22Spectrum Sensing DTV Detection Results based CyclostationaryFeature Detection
Pd = >99%, Pfa =
10%, -20dB
June 2010
Apurva N. Mody, BAE SystemsSlide 11
-130
-125
-120
-115
-110
-105
-100
-95
0.1 1 10 100
Minimum sensing time (ms)
Sensingthreshold(dB
m)
TG1
certificate
TG1
signature
TG1 information
(FEC encoded)
Sync and index
8-chip spreading
sequence
1-Energydetection
1-Energydetectioncorrelatedonspreadsequence
Wireless Microphone Beacon Sensing Results
-114 dBm
TV and Wireless Microphone Protection Using SpectrumSensing
FCC R&O requires
DTV protection at -114 dBm in 6 MHz of bandwidth. This amounts toan SNR of -19 dB for equivalent receiver noise figure of 11 dB and 22dB safety margin at edge of coverage
Wireless microphone protection at -114 dBm in 200 kHz bandwidth.This amounts to an SNR of -3 dB for equivalent. recceiver noise figureof 11 dB.
Several blind and signal specific feature-based sensing schemes havebeenproposed and thoroughly evaluated using TV Broadcaster supplied
over-the-air collected signals Spectral correlation based sensing,
Time domain cyclostationarity,Eigen value based sensing,FFTbased pilot sensing,Higher order statistics based sensing, etc.
Wireless Microphone Protection Using Beacon (IEEE802.22.1 StandardNearly Complete)
Many studies have suggested that FCC R&O target for wirelessmicrophones is not sufficient to protect wearable microphones(wherebody attenuation of as much as 27dB is possible according tothe manufacturers)
802.22 has designed a beacon signal which will be transmitted fromwireless microphone base stations with 250 mW (as compared to 10mW for microphones). These beacon signals consist of repeated
pseudo-noise (PN) sequences and occupy a bandwidth of 78 kHz.
Security features are provided for beacon authentication
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IEEE 802.22Geo-location
Satellite-based geo-location Requires GPS antenna at each terminal
NMEA 0183 data string used to report to BS
Poor accuracy in Northern hemispheres.
Terrestrially-based geo-location: A new scheme has been proposed requiring no additional
hardware and using the characteristics and capabilities of
the 802.22 standard.
Normal BS-CPE ranging process:provides coarse ranging
to an accuracy of147.8 ns (44.3 m) Extended BS-CPE ranging process: augments the accuracy
of the ranging process to 1 ns (0.3 m)by a more accurate
scheme using the complex channel impulse response
received at the CPE (Vernier-1) and at the BS (Vernier-2)
Extended CPE-CPE ranging process: new scheme using
the preamble of the CBP burst transmitted by a CPE and
captured by another CPE in the surrounding area to acquirethe distance between CPEs with a high level of accuracy
(Vernier-3)
Off-line geo-location calculation: All the information
acquired at the CPEs is transmitted to the BS which can
delegate the calculation of the CPE geo-location to a
server. Calculation is based on usual triangulation using
some CPEs as waypoints.
List of echo amplitudes and delaysrelative to the terminal 2 sampling time
IDFT
Time
QI
Time
Cyclic prefix
Convolution with thechannel impulse response
Time
QI
QI
2048 samples
QI
QI
QI
Complex
correlation
OFDM carrier setdistorted by channel
Frequency
...
QI
Frequency domain response of aDirac pulse distorted by channel
Frequency
...
Carrier phase reversal
based on the PN-sequence
IDFT
Channel impulse r esponserelative to the sampling time
QI
QI
QI
QI
1
QI
123 Amplitude1 Delay1Amplitude2 Delay2Amplitude3 Delay3
Amplitude4 Delay4etc...
Y
Y/X
2048 carriers BPSKmodulated by PN- sequence
2048 time domain samples
2048 carriers
2048 carriers
2048 I&Q samples at samplingperiod (i.e., every 180 degrees)
High r esolution bandlimited impulse response
(e.g., every 1 degree)
QI
2048 x 1 80 I&Q samplesat every degreeQI
DFT
Signal transmittedto terminal 2
Signal sent back to terminal 1
Frequency
...X
PN-sequence
Signal receivedby the u ser terminal
OFDM carrier set
Resolution= sampling period / 180
-
1
0
1
PrecisetimesampleImaginary
Real
-1
0
1
I
Q
Samplingtimes
Imaginary
Real
Channel impulse r esponserelative to the sampling time
12
Signal Processing Flow for the Terrestrial
Geo-location
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Apurva N. Mody, BAE SystemsSlide 12
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IEEE 802.22Self Co-existence
time
Cell 1 Cell 2 Cell 3 Cell 3 Cell 1 Cell 2 Cell 1 Cell 1 Cell 2 Cell 3
Super-frame N (16 Frames) Super-frame N+1 (16 Frames)
Coexistence Beacon WindowsData Frames
TV Channel
X
Spectrum Etiquette(Enough channels available)
On Demand Frame
Contention(Two or more cells need to co-exist on
the same channel)
Number xrepresents operating channel
Number yrepresents backup channel
Number z (double underline)represents candidate channel
Primary user
appears
Requires that information on
operating, backup and candidate
channels of each cell is shared
amongst WRAN cells:exchanged by CBP bursts.
Self-coexistence window
(SCW) does not have to
be allocated at each
frame.
June 2010
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Confidentiality and PrivacyAES (128) GCM is
used for encryption and authentication
Network Authorization - RSA and ECC based X.509certificates are used for mutual authentication /
network entry authorization.
IntegrityAES-GCM is used to compute Integrity
Check Vector (ICV). PN sequence numbers are
appended to each packet.
AuthenticationSignals such as wireless
microphone beacon and CBP are authenticated using
ECC based digital signatures. No encryption is
provided for these packets
Key Management - Secure Control and Management
Protocol is used for key management.
Management MessagesAll management messages
except for the broadcast, initial ranging and basic
CID are protected.
Device Security - Trusted Computing Group,Trusted Platform Module specifications are
recommended to enable tamper-proof capability for
hardware and software.
IEEE 802.22Security Sub-layer 1 (Non-Cognitive)
Security Sub-layer 1
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Spectrum Availability - Spectrum Sensing used to ensure spectrum
availability for primary users.
Various types ofsignal specific and feature based
sensing algorithms have been included into the
standard
Standard recommends sensing algorithms to
determine the signal type (Signal Classification)
Collaborative Sensing - The group in general thinks
that collaborative sensing will be useful. FCC R&O
requires OR rule based collaborative sensing. Correlation with Geo-location Information
Closely tied to collaborative sensing. It tries to
cross check the spectral footprint of the detected
signal based on location of the sensor
Spectrum Access Authorization BS is capable of de-authorizing a subscriberat any
time. Sensing and incumbent database service usedfor spectrum access authorization
Capability CheckThe Spectrum Manager (SM) is
capable of prohibiting a subscriber from registering
if it does not have adequate sensing capabilities.
Radio Behavior Control IEEE 802.22 ispolicy driven. Policies are rule-
based.
IEEE 802.22Security Sub-layer 2 (Cognitive)
Security Sub-layer 2
Signal
classificationand policy
based
behavior
control of the
802.22 devices
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June 2010
Apurva N. Mody, BAE SystemsSlide 16
References
IEEE 802.22 Working Group Websitewww.ieee802.org/22
J. Mitola, Cognitive Radio: An Integrated Agent Architecture for Software Defined
Radio, Ph. D. Thesis, Royal Institute of Technology, Sweden, Spring 2000.
Gerald Chouinard, Communications Research Center, 802.22 Overview presentation to
the 802 Whitespaces Study Group https://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-
whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppt
IEEE 802.22 Draftv3.0Members only Documents of the IEEE 802.22 Working Group(www.ieee802.org/22)
Other Contributions to the IEEE 802.22 Standard (www.ieee802.org/22)
http://www.ieee802.org/22https://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttp://www.ieee802.org/22http://www.ieee802.org/22http://www.ieee802.org/22http://www.ieee802.org/22https://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttps://mentor.ieee.org/802-sg-whitespace/dcn/09/sg-whitespace-09-0058-00-0000-802-22-presentation-to-ecsg.ppthttp://www.ieee802.org/22