Doc.: sg-whitespace 09-0058r2 Submission March 2009 Gerald Chouinard, CRCSlide 1 802.22 Presentation to the ECSG on White Space Author: Notice: This document

March 2009

Gerald Chouinard, CRC

Slide 1

doc.: sg-whitespace 09-0058r2

Submission

802.22 Presentation to the ECSGon White Space

Name Company Address Phone email Gerald Chouinard Communications

Research Centre, Canada

3701 Carling Ave. Ottawa, Ontario Canada K2H 8S2

(613) 998-2500 [email protected]

Author:

Notice: This document has been prepared to assist IEEE 802.22. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this 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 IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s 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 802.11.

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 the statement "IEEE standards may include the known use of patent(s), including patent applications, 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 publication will be approved for publication. Please notify the Chair Carl R. Stevenson <[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 802.11 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at <[email protected]>.

AbstractThis contribution illustrates the work carried out by the 802.22 WG over the last 5 years in developing the Wireless Regional Area Network standard to be used in TV White Space.

March 2009


Slide 2


Submission

Outline

1. The IEEE 802.22 WRAN Standard

2. Coexistence among communication systems in TV White Space

a) Protection of TV broadcasting

b) Protection of Part 74 wireless microphones

c) 802.22.1 wireless microphone beacon

d) Quiet periods for sensing

e) Self-coexistence among WRAN systems

3. Further observationsa) DTV coverage protection

b) RF mask

March 2009


Slide 3


Submission

IEEE 802.22

RAN

“Regional Area Network”

IEEE Standards

30 km

54 - 862 MHz

Multipath absorption Window

(Cyclic prefix )

0.252.2 μsec

0.8

37 μsec

23 Mbit/sBW= 6,7,8 MHz

March 2009


Slide 4


Submission

Rural Broadband:- Cable-modem / ADSL- WiFi hot-spots in ISM bands

- Higher power, lower frequency broadband access system

30 km23 km

16 km

MACLong round-trip

delays

QPSK

16-QAM64-QAM

PHYAdaptive

modulation

- Medium power wireless systems

5 km

March 2009


Slide 5


Submission

Typical CPE installation (Fixed)Sensing antenna

GPS antenna

TX/RX WRAN Antenna

March 2009


Slide 6


Submission

802.22 Frame

Structure frame 0

Superframe n-1 Superframe n Superframe n+1

SuperframePreamble

SCH

. . .

FramePreamble

160 ms

frame 1

10 ms

frame 15

DS sub-frame

TTG

RTG

US sub-frame(smallest US burst portion on a given subchannel= 7 symbols)

26 to 42 symbols corresponding to bandwidths from 6 MHz to 8 MHz and cyclic prefixes from 1/ 4 to 1/ 32

Fram

e Pr

eam

ble

FCH

DS-

MAP

Burs

t 1DCD

Burs

t 2

tim

e bu

ffer

tim

e bu

ffer

Self-c

oexi

sten

ce w

indo

w (

4 o

r 5 s

ymbol

s w

hen

sch

edule

d)

Burst 1

60 s

ubch

anne

ls

Burst 2

Burst 3

more than 7 OFDMA symbols

Burst

Burst n

Burst

Burs

t m

Ranging/ BW request/ UCS notification

Burst

Burst

Bursts

Burs

ts

... Time...

US-

MAP

US-

MAP

UCD

10 ms 10 ms

FramePreamble

FramePreamble

Superframe = 160 ms

Frame= 10 ms

Superframe =16 frames

March 2009


Slide 7


Submission

802.22 Reference Architecture

March 2009


Slide 8


Submission

Outline









b) RF mask

March 2009


Slide 9


Submission

Coexistence among communications systems in TV White Space

Self-coexistence

DTVAnalog

TVWireless

MicrophonePLMRS 802.11 802.15 802.16 802.22 DOCSIS etc.

802.11 802.11

802.15 802.15

802.16 802.16h

802.22 802.22 802.22 802.22 SG-09-43r1 SG-09-43r1 SG-09-43r1 802.22

DOCSIS

etc.

LegendProtection of incumbentsSelf-coexistenceCoexistence among IEEE 802 systemsCoexistence with non-IEEE 802 systemsCoexistence among non-IEEE 802 systems

Incumbent protection Coexistence

March 2009


Slide 10


Submission

Outline









b) RF mask

March 2009


Slide 11


Submission

WRAN CPE and DTV protection

DTV WRAN

March 2009


Slide 12


Submission

DTV TX(1 MW ERP, 300 m)

118 km

41 dB(uV/m)F(50, 90)

4 W WRAN

Base Station

16.8 km

16.2 km

4 W WRAN base station

keep-out distance

36.3 dB(uV/m)

WRAN keep-out distance:Minimum field strength: 41 dB(uV/m)Protection ratio: 23 dBCPE antenna front-to-back: 14 dBInterfering field strength: 32 dB(uV/m)

Co-channel keep-out distance between DTVand 802.22 WRAN

Geolocation & Database

134.2 km

March 2009


Slide 13


Submission

TV sensing techniquesstudied by 802.22

• Blind– Energy detection– Eigenvalue sensing (I2R)

• Multi-resolution (MRSS)

• Spectral correlation– Sensing for one TV band

– Sensing procedure for TV signals

– Sensing for multiple TV channel band

• Selection of frequency components: emphasizing near Parts with abrupt changes

• ATSC cyclostationary sensing technique

Signal specific– ATSC Sequence correlation sensing

•ATSC signature•Pilot recovery•Single ATSC data field•Multiple ATSC data fields•Sync segment

– ATSC FFT-based Pilot sensing (Philips)– ATSC Pilot sensing technique using high order statistics– ATSC PLL-based Pilot sensing technique

•Dual FPLL pilot sensing

– ATSC Pilot covariance sensing technique•Covariance based sensing

– Higher order statistics based pilot detection

March 2009


Slide 14


Submission

DTV Broadcast Incumbent SensingATSC FFT-based Pilot Sensing Technique

(Philips)

1 ms sensing window will allow a 32-point FFT while a 5 ms window will allow a 256-point FFT

0

x(t)

0

y(t)

53.8 kHz-53.8 kHz

……

21.52 MHz-21.52 MHz

……

FFT applied around the pilot carrier

Method 5 ms 10 ms 30 ms 50 ms

Pilot-Energy -18 dB -20.5 dB -23.5 dB -24.5 dB

Pilot-Location (NT=2) --- -18.5 dB -22.0 dB -24.0 dB

Required SNR for DTV signal detection

March 2009


Slide 15


Submission

DTV Broadcast Incumbent SensingSensing techniques performance comparison

RF 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)

Pro

ba

bili

ty o

f m

isd

ete

cti

on

(P

md

)

Energy - 1dB Pfa=10% 5 ms

Energy - 0.5dB Pfa=10% 5 ms

Energy - 0dB Pfa=10% 5ms

Thomson-Segment Pfa=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

March 2009


Slide 16


Submission

Outline









b) RF mask

March 2009


Slide 17


Submission

WRAN coverage and co-channel operation with wireless microphones

R1

R2

Minimum WRAN field strength: 29 dB(uV/m)

Edge of coverage of the WRAN BS

(e.g., 17 km for 4 W EIRP, 30 km for 100 W EIRP)

Area where CPEs need to change

frequency

Area where CPEs need to reduce their transmit power as a function of their distance to the wireless microphone

operation

Wireless microphone operation

R2

F(50, 99.9)

F(50, 10)

March 2009


Slide 18


Submission

Wireless microphone sensing techniques studied by 802.22

• Signal specific• Wireless microphone covariance sensing

technique– Covariance based sensing

– Covariance absolute value detection

– Covariance Frobenius norm detection

• Spectral correlation sensing technique• Sensing for one TV band

– Sensing Procedure for wireless microphone signals

March 2009


Slide 19


Submission

Outline









b) RF mask

March 2009


Slide 20


Submission

802.22.1 Beacon Design

Inter-beacon networking

period

I-channel

Q-channel

3.33 ms

98 ms

- Source address- Location- subchannel map- signature- certificate

101 ms frame

March 2009


Slide 21


Submission

802.22.1 Beacon Design

PPDU (101 octets)

Location Signature Certificate

March 2009


Slide 22


Submission

Detection of the 802.22.1 beacon

-130

-125

-120

-115

-110

-105

-100

-95

0.1 1 10 100

Minimum sensing time (ms)

Sen

sin

g t

hre

sho

ld (

dB

m)

TG1certificate

TG1signature

TG1 information(FEC encoded)

Sync and index

8-chip spreadingsequence

1 - Energy detection

1 - Energy detection correlated on spread sequence

-114 dBm

March 2009


Slide 23


Submission

Outline









b) RF mask

March 2009


Slide 24


Submission

802.22 Frame

Structure frame 0


SuperframePreamble

SCH

. . .

FramePreamble

160 ms

frame 1

10 ms

frame 15

DS sub-frame

TTG

RTG

US sub-frame(smallest US burst portion on a given subchannel= 7 symbols)


Fram

e Pr

eam

ble

FCH

DS-

MAP

Burs

t 1DCD

Burs

t 2

tim

e bu

ffer

tim

e bu

ffer

Self-c

oexi

sten

ce w

indo

w (

4 o

r 5 s

ymbol

s w

hen

sch

edule

d)

Burst 1

60 s

ubch

anne

ls

Burst 2

Burst 3

more than 7 OFDMA symbols

Burst

Burst n

Burst

Burs

t m

Ranging/ BW request/ UCS notification

Burst

Burst

Bursts

Burs

ts

... Time...

US-

MAP

US-

MAP

UCD

10 ms 10 ms

FramePreamble

FramePreamble

Superframe = 160 ms

Frame= 10 ms


March 2009


Slide 25


Submission

802.22 Frame

Structure frame 0


SuperframePreamble

SCH

. . .

FramePreamble

160 ms

frame 1

10 ms

frame 15

DS sub-frame

TTG

RTG

US sub-frame


Fram

e Pr

eam

ble

FCH

DS-

MAP

Burs

t 1DCD

Burs

t 2

60 s

ubch

anne

ls

... Time...

US-

MAP

US-

MAP

UCD

10 ms 10 ms

FramePreamble

FramePreamble

Burst 1

Burst 2

Burst 3

Burst 4

Ranging/ BW request/ UCSnotification

Bursts

Quiet Period

Frame quiet period: 5.1 ms

Superframe = 160 ms

Frame= 10 ms


March 2009


Slide 26


Submission

802.22 Superframe Structure

frame 0


. . .

160 ms

frame 1

10 ms

frame 15

... Time...

10 ms 10 ms

Quiet Period Quiet Period

Multi-frame quiet periods

March 2009


Slide 27


Submission

802.22 Superframe Structure

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

Superframe quiet period: up to 158 ms

March 2009


Slide 28


Submission

Outline









b) RF mask

March 2009


Slide 29


Submission

WRAN Self-coexistence considerations

Different TV channel selection for operational channel and

first backup channel

Frame allocation signalledby the superframe control

header (SCH)

MAC self-coexistence schemes PHY coexistence mechanisms

Spectrum Etiquette

Frame contention

Spectrum Etiquette

Frame-based On-demand Spectrum contention

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

March 2009


Slide 30


Submission

Coexistence Beacons for Inter-WRAN Communications

• Inter-cell communication mechanism to keep BSs aware of the other nearby WRAN cell operation:

– Coexistence beacon• Transmitted during the self-coexistence windows at the end of

some frames by the BS and/or some designated CPEs

• Monitored by BSs and other CPEs from same and different cells on same channel or different channel for future channel switching

• Signals IP address of BS and CPE every 15 min. as asked by R&O

Coexistence Beacon Protocol (CBP) burst

Symbol

Preamble CBP MACPDU

(Optional)

CBP MACPDU

Extension of

March 2009


Slide 31


Submission

Inter-WRAN Communications Scenarios(Require Neighbor-cell CPEs to exist)

WRAN2 WRAN1

BS2BS1CPE1

CPE2

• The “face-to-face CPEs” case:

• The “back-to-back CPEs” case:

WRAN2 WRAN1

BS1BS2 CPE1CPE2

March 2009


Slide 32


Submission

Outline









b) RF mask

March 2009


Slide 33


Submission

DTV Coverage: Athen, GA

News Corporation’s Fox Technology Group’s propagation prediction software: 22-05-0083-00-0000-tv-simulation-results.doc

Noise Limited Contour

DTV Coverage: Athen, GA

March 2009


Slide 34


Submission

CPE RF Emission Masks

-110

-100

-90

-80

-70

-60

-50

-40

-30

-20

-10

0

-2.5 -1.5 -0.5 0.5 1.5 2.5

Channel Spacing

Lev

el r

elat

ive

to i

n-b

and

po

wer

den

sity

(d

B)

802.22

802.22 Micro

802.22 Ext.

CDN Mask

CDN Relaxed Mask

802.16

FCC Mask

Part 15.209a

Center line

802.22 RF Mask

1 dB DTV RX desensitization

4 Watt EIRP

Rejection if microphones in 1st adjacent channel

33 dB

March 2009


Slide 35


Submission

References1. IEEE P802.22™/ DRAFTv1.0 Draft Standard for Wireless Regional

Area Networks Part 22: Cognitive Wireless RAN Medium Access Control (MAC) and Physical Layer (PHY) specifications: Policies and procedures for operation in the TV Bands, April 2008

2. FCC R&O 08-260

Documents

Doc.: sg-whitespace 09-0058r2 Submission March 2009 Gerald Chouinard, CRCSlide 1 802.22 Presentation to the ECSG on White Space Author: Notice: This document