cognitive radio technology & ieee802.22 …b1%… · · 2012-03-20cognitive radio technology...
TRANSCRIPT
2::: ETRI, The Future Wave ::: 디지털방송연구단
목 차
q CR 기술 개요ü 주파수 자원의 이용현황
ü CR 기술과 전파이용
ü CR 응용
q IEEE802.22 표준 회의ü Functional Requirement
ü Proposal 제안 현황 및 진행 경과
ü Joint Proposal
q향후 일정
4::: ETRI, The Future Wave ::: 디지털방송연구단
Definition of Cognitive Radio
▣ Cognitive Radio (NTIA)◈ A Radio or system that senses its operational
electromagnetic environment and can dynamically and autonomously adjust its radio operating parameters to modify system operation, such as maximize throughput, mitigate interference, facilitate interoperability, access secondary markets.
5::: ETRI, The Future Wave ::: 디지털방송연구단
Adaptive radioscan adjust themselves to accommodate anticipated events
Fixed radiosare set by their operators
Cognitive radioscan sense their environment and learn how to adapt
Beyond adaptive radios, cognitive radios can handle unanticipated channels and events.
Cognitive radios require:• Sensing• Adaptation• Learning
Cognitive radios intelligently optimize their own performance in response to user requests and in conformity with FCC rules.
What is a Cognitive Radio?
6::: ETRI, The Future Wave ::: 디지털방송연구단
주파수 분배 및 이용
▣ 한정된 전파자원▣ Spectrum licensing: Exclusive rights▣ Access limited è Throughput limited
7::: ETRI, The Future Wave ::: 디지털방송연구단
주파수 이용 측정
No signals Medium and short duration signals
FCC Should Conduct and
Publish Spectrum Occupancy
Measurements to Identify Low
Occupancy Bands
“In many bands, spectrum access is a more significant problem than physical scarcity of spectrum, in large part due to legacy command-and-control regulation that limits the
ability of potential spectrum users to obtain such access.”— FCC Spectrum Policy Task Force Report
8::: ETRI, The Future Wave ::: 디지털방송연구단
스펙트럼 이용 측정
▣ Some spectrum is intensively used
▣ Other spectrum has highly variable use in when viewed in terms of time and geography
9::: ETRI, The Future Wave ::: 디지털방송연구단
Easement User
2nd-aryUser
2nd-aryUser
Licensee
Not-to-Interfere Basis
Below the Acceptable “Interference Temperature”
CR 기술과 전파이용
10::: ETRI, The Future Wave ::: 디지털방송연구단
Cognitive Radio 개념Cognitive Radio 개념
전파 환경을 측정(Observe) 하고, 그 환경에 적합한 방향(Orient) 을설정, 이 중 최적의 방안을 스스로 결정(Decide)하고, 통신(Act) 하는기술 (OODA Loop): 타 기기에 간섭을 주지 않는 조건
전파 환경을 측정(Observe) 하고, 그 환경에 적합한 방향(Orient) 을설정, 이 중 최적의 방안을 스스로 결정(Decide)하고, 통신(Act) 하는기술 (OODA Loop): 타 기기에 간섭을 주지 않는 조건
User2’ User3
12::: ETRI, The Future Wave ::: 디지털방송연구단
Cognition Cycle
Observe
OrientEstablish Priority
Plan
Decide
ActOutsideWorld
Send a Message
Receive a Message
Set Display
Read Buttons Save Global States
Allocate Resources
Initiate Process(es)(Isochronism Is Key)
Generate Alternatives(Program Generation)
Evaluate AlternativesParse
Pre-process
Infer on Context Hierarchy
UrgentImmediate
Normal
Register to Current Time
PriorStates
NewStates
Learn
[Mitola, Ph. D dissertation defense materials, Royal Institute of Technology, 2000]
13::: ETRI, The Future Wave ::: 디지털방송연구단
Cognitive Radio Overview
WidebandA/D-D/A*
Wideband RFConversion
ProgrammableProcessor(s)
Software Radio
J. Mitola : “Software Radio: Technology and Prognosis ”Proc., IEEE National Telesystems Conference 1992“Software Radio Architecture”IEEE Communications Magazine, May 1995Cognitive Radio, Licentiate Thesis,KTH (Royal Institute of Technology), Stockholm
HF LVHF VHF-UHF Cellular Indoor & RF LAN VHDR
2 MHz 28 88 400 960 MHz 6 34 GHz1.39 GHz
PCS
2.5 5.9
Software Radios Very Low Band Low Mid Band High Band
Cellular Mobile
Public Safety
Fixed Terrestrial
4 Channels
Antenna RF ModemINFOSEC
BasebandUser Interface
Model-Based ReasoningRKRL Frames
Spatial &Temporal
Knowledge
14::: ETRI, The Future Wave ::: 디지털방송연구단
Improved Link Reliability
▣ Cognitive radio is aware of areas with a bad signal
▣ Can learn the location of the bad signal◈ Has “insight”
▣ Radio takes action to compensate for loss of signal◈ Actions available:
– Power, bandwidth, coding, channel
◈ Radio learns best course of action from situation
Good Transitional PoorSignal Quality
§ Can aid cellular system§ Inform system & other radios of identified gaps
15::: ETRI, The Future Wave ::: 디지털방송연구단
응용 분야응용 분야
Ø 기존 WLAN 주파수 이용 효율 증대에 CR 기술 이용Ø IEEE 802.11h에서 채널 측정 기능을 포함한 효율적 이용 기술 표준화 중Ø 기존 WLAN 주파수 이용 효율 증대에 CR 기술 이용Ø IEEE 802.11h에서 채널 측정 기능을 포함한 효율적 이용 기술 표준화 중
Ø IEEE 802.22에서 미사용 TV 대역 스펙트럼 이용: CR 기술 표준화 시작(’04년 11월 kick-off 회의, ’05년 1월 Monterey/3월 Atlanta 회의) Ø 응용서비스: 33 km이내 지역까지의 고속 인터넷 서비스, 비 허가 추진
Ø IEEE 802.22에서 미사용 TV 대역 스펙트럼 이용: CR 기술 표준화 시작(’04년 11월 kick-off 회의, ’05년 1월 Monterey/3월 Atlanta 회의) Ø 응용서비스: 33 km이내 지역까지의 고속 인터넷 서비스, 비 허가 추진
WRAN(Wireless Regional Area Network)WRAN(Wireless Regional Area Network)WRAN(Wireless Regional Area Network)
WLANWLANWLAN
ØInterference Temperature Limit 적용: 가능한 대역 활용Ø 비 간섭 조건으로 출력 증가 커버리지 확대, 응용 서비스 다양화
(미국은 기존 출력의 4배까지 허용)
ØInterference Temperature Limit 적용: 가능한 대역 활용Ø 비 간섭 조건으로 출력 증가 커버리지 확대, 응용 서비스 다양화
(미국은 기존 출력의 4배까지 허용)
비 면허 기기비비 면허면허 기기기기
Ø 공공 안전/재난 통신: 평상시 타 목적 이용, 비상시 충분한 채널 확보하여 사용Ø 군용 통신망: 작전이나 해외 파견 시 미 사용 주파수 탐색/활용Ø 이 기종 무선통신망 연동에 응용
Ø 공공 안전/재난 통신: 평상시 타 목적 이용, 비상시 충분한 채널 확보하여 사용Ø 군용 통신망: 작전이나 해외 파견 시 미 사용 주파수 탐색/활용Ø 이 기종 무선통신망 연동에 응용
기 타기기 타타
16::: ETRI, The Future Wave ::: 디지털방송연구단
CMRSPublic SafetyData Services
Data Se
rvice
s
Public Safety
CMRS
1% 10% 100% 10% 1%
1%
10%
100%
Duty Cycle
Use of public safety spectrum is highly variable
Flexible Spectrum Use
ØIllustration: Public Safety & Dynamic Spectrum Use
18::: ETRI, The Future Wave ::: 디지털방송연구단
IEEE802.22 표준
q Kick-off meeting(’04.11.)q Interim meeting(’05.1.): Schedule 협의
q Plenary Meeting(’05.3): Functional Requirementsq Interim meeting(’05.9): Call For Proposalq Proposal 접수: ’05.11.
q 9 Proposals
q Merged Proposal: ’06.1q ETRI-FT-I2R-Phillips-Samsung-Thomson
q Runcom/STMicro
q Down-selection Process: ’06.3~
19::: ETRI, The Future Wave ::: 디지털방송연구단
Overview of IEEE 802.22q Scopel 54~862MHz(Unused TV Band)에서 동작하는 Fixed P-MP WRAN(Wireless
Regional Area Network)의 PHY, MAC 규격 정의
q목적lWRAN 시스템의 호환성 확보 및 multivendor화lWireline broadband access에 대한 대체 수단을 제공하여 broadband access
시장 경쟁 촉진l인구 밀도가 낮은 지역을 포함하여 건물이 산재해 있는 지역에 Wireless
broadband access 시스템 시설을 용이하게 함 (dense area는 검토 중)
q Working Group Officersl Chair : Carl R. Stevenson, WK3C Wireless LLC, [email protected])l Vice-Chair : Gerald Chouinard, CRC, [email protected] Secretary : Ashish Pandharipande, Samsung Advanced Institute Of
Technology, [email protected]
q Ad Hoc Groupl General : Gerald Chouinard, CRC, [email protected] MAC : Carlos Cordeiro, Philips, [email protected] PHY : Eli Sofer, Runcom, [email protected]
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q Provide Broadband Access to one or more core network rather
than forming the end-to-end communication system
o Capability: Similar to ADSL and cable modem over less
propagated rural areas(1.25 person/km2)
o Service Range: typically 33 km, maximum 100 km
o Fixed location customers: geographically fixed, re-locatable, or
nomadic
o Point-to-Multipoint (P-MP) radio interface
o VHF/UHF TV broadcast bands: 41 MHz ~ 910 MHz
o Near- and Non-line-of-sight communication: Due to foliage
q Standardization Target
o 802.22 MAC & PHY between base station and subscribers
(not between base stations)
서비스 모델서비스 모델
22::: ETRI, The Future Wave ::: 디지털방송연구단
Public IP Network
Service Provider IP Network
HAAAA
SD
ACR ACR
WRANBS
CPE
WRAN Hierarchy
•AAA : Authentication, Authorization and Account Server •ACR : Access Control Router HA : Home Agent
23::: ETRI, The Future Wave ::: 디지털방송연구단
WRANRepeater
TV TransmitterWRAN
Base Station
WirelessMIC
WirelessMIC
WRANBase Station
: CPE
: WRAN Base Station
Typical ~33kmMax. 100km
Deployment Scenario
26::: ETRI, The Future Wave ::: 디지털방송연구단
Multiple Access TechniquesMultiple Access Techniques
qDuplex Mode
§ Standard must support duplex mode of operation.
§ If FDD is proposed, the proposal must include band plan
or propose a scheme to do it.
qFlexible Asymmetry
§ Internet Access: Most of capacity is consumed in the
downstream direction
§ Surveillance video from CPE: Upstream
§ Telephony and video conferencing: Symmetrical capacity
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주요 시스템 변수주요 시스템 변수
q Frequency Range: 41~910 MHz
q Channel Bandwidth: 6, 7, 8 MHz
q Base Station: Transmitter
§ Antenna Gain: 18 dBi
§ Antenna Height: 75 or 150 m HAAT
§ Cable loss: 3 dB
q Base Station: Receiver
§ Antenna Gain & Antenna Height: Same as the transmitter
§ LNA NF: 2.5 dB
§ Interference Allowance: 2 dB
§ Receiver Figure of Merit: -11 dB/K
28::: ETRI, The Future Wave ::: 디지털방송연구단
Coexistence & interference mitigation
-116dBm(6MHz BW) for DTV-107 dBm (200kHz BW)Interference Detection Threshold
100 msec100 msecChannel Closing Transmission Time
(Aggregate transmission time)
2 sec2 secChannel Move Time (In-service
monitoring)
100 msec100 msecChannel Opening Transmission Time (Aggregate transmission time)
2 sec2 secChannel Setup Time
<=2 sec to >=90% PD with False Alarm rate of <=10%
<=2 sec to >=90% PD with False Alarm rate of <=10%
Channel Detection Time
10 minutes (recommended)10 minutes (recommended)Non-Occupancy Period
30 sec (recommended)30 sec (recommended)Channel Availability Check Time
Value for TV BraodcastingValue for Part 74 DevicesDFS Parameters
l DFS Timing requirements
29::: ETRI, The Future Wave ::: 디지털방송연구단
Joint Proposal
◈ ETRI, SEM, GIT◈ Samsung ◈ Phillips, French Telecom◈ I2R◈ Runcom, STMicro◈ NextWave◈ Hawei
30::: ETRI, The Future Wave ::: 디지털방송연구단
System Overview
▣OFDMA both in uplink and downlink▣2K FFT mandatory▣TDD mandatory, FDD optional▣10 msec frame duration ▣16-frame superframe▣QPSK, 16-QAM, and 64-QAM, transformed-QPSK ▣Rate 1/2 through rate 5/6 coding▣30 - 32 sub-channels per TV channel▣Data rate range from 4.8Mbps to 72.6Mbps (with
optional channel bonding and channel aggregation)
31::: ETRI, The Future Wave ::: 디지털방송연구단
Optional fractional use of TV channel and channel bonding up to 3 contiguous TV channels. Channel aggregation of discontiguous channels.
▣ Mandatory: 6, 7, 8 MHzBandwidth
Point-to-Multipoint Network
TDD mandatory
1/4, 1/8, 1/16, 1/32
2K mandatory
Adaptive OFDMA
Default 4W EIRP
QPSK, 16QAM, 64QAM mandatory
▣ Maximum: 4.03 bits/s/Hz▣ Minimum: 0.81 bits/s/Hz
▣ Maximum: 72.6 Mbps▣ Minimum: 4.8 Mbps
Typical range 33 km
54~862 MHz
Specification
Cyclic Prefix Mode
1K / 4K optional, 2K / 4K / 6K for channel bonding FFT Mode
Partial bandwidth allocationMultiple Access
Single TV channel BW of 6 MHzSpectral Efficiency
Service coverage
FDD supportedDuplex
Transmit power
Network topology
Modulation
Maximum of 23 Mbps for 6 MHzData rate
Frequency range
RemarkParameters
System Parameters
32::: ETRI, The Future Wave ::: 디지털방송연구단
Adaptive OFDMA
▣ Flexible Bandwidth Allocation using FFT◈ Channel bonding◈ Fractional bandwidth usage
▣ Adaptive resource allocation according to user environments◈ Channel selectivity
33::: ETRI, The Future Wave ::: 디지털방송연구단
Fractional Bandwidth Usage
• Considering the location, bandwidth and type of the narrowband incumbent users, we can use the fractionally vacant bandwidth of a single channel
• The number of used sub-carriers is proportional to the fractional bandwidth
• If the wireless microphones are operating co-channel, the WRAN systems shall clear the entire channel
• The fractional BW mode is identified by using a Preamble• Example:
6 MHz Unused(6 MHz)6 MHz
f
Incumbent or other CR user(except microphone user)
TV incumbent user Microphone userFractional useof TV channel
GuardBand
Other CR user or non-microphone incumbent (regulations permitting)
34::: ETRI, The Future Wave ::: 디지털방송연구단
Subchannelization
Subcarrier Allocation
AdjacentSubcarrier Permutation
AdjacentSubcarrier Permutation
Uniformly DistributedSubcarrier permutationUniformly DistributedSubcarrier permutation
Scattered typeScattered typeBand typeBand type
•Each subchannelconsists of distributed subcarriers within an OFDM symbol
•Only the average CINR over all subcarriers is required
•For users with high frequency selectivity or far distant users
•Each subchannelconsists of a group of adjacent subcarriers
•Bands in good state are selected for data transmission
•Multiuser diversity•Require more feedback
information than distributed subcarrier allocation type
DistributedSubcarrier permutation
AdjacentSubcarrier Permutation
35::: ETRI, The Future Wave ::: 디지털방송연구단
frame n-1 frame n frame n+1 ...Time
...
MAC Slot Number
Pre
ambl
e
FCH
DS
-MA
PU
S-M
AP
Se
lf-co
exi
ste
nce
Ranging
UCS Notification
Burst CPE #4
Burst CPE #2
Burst CPE #1
Burst CPE #5
Burst CPE #3
Burst CPE #7
Burst CPE #1
Burst CPE #2
Burst CPE #4
Burst CPE #5
Burst CPE #3
Burst CPE #6
Burst CPE #8
Burst CPE #9
Se
lf-co
exis
ten
ce
Burst CPE #6
Burst CPE #7
Burst CPE #8
TTG
k k+1 k+3 k+5 k+7 k+9 k+11 k+13 k+15 k+17 k+20 k+23 k+26 k+29
TV Channel N
TV Channel N+1
DS US
Log
ica
l MA
C C
han
ne
l Nu
mb
er
s
s+1
s+2
s+L
BW Request
RTG
Frame Structure
36::: ETRI, The Future Wave ::: 디지털방송연구단
Superframe Structure
Superframe n-1 Superframe n Superframe n+1 ...Time
...
Preamble SCH frame 0 frame 1 frame m...
TV Channelt-1
TV Channelt
TV Channelt+1
Time
Preamble SCH
Preamble SCH
Fre
quen
cy
Preamble SCHFrame
0Frame
1
Framem-2
(Quiet)...
... Frame0
Frame1
Preamble SCH
Preamble SCH
Occupied by Incumbent
Occupied by Incumbent
Framen
Occupied by Incumbent
Framem
Framem-1
37::: ETRI, The Future Wave ::: 디지털방송연구단
Frame Element Definitions
▣ Preamble – synchronization, channel estimation◈Long training sequence and optional short training
sequence◈There’s also an upstream burst preamble
▣ FCH – frame control header, info on size of DS- and US-MAP and channel descriptors (PHY characteristics)
▣ MAPs – resource scheduling info for user bursts▣ Ranging – timing offset, power adjustment▣ UCS – urgent coexistence situation, incumbent detection
report▣ BW Request – self-explanatory▣ SSS - sliding self-coexistence slots – used by coexistence
beacon to improve coexistence with neighbors ▣ BCH – burst control header for upstream – ID information
38::: ETRI, The Future Wave ::: 디지털방송연구단
Channel Coding
▣ Convolutional Coding (mandatory)◈Rate ½ , other rates by puncturing◈Constraint length 7
▣ Optional Advanced Codes◈Duo-binary Convolutional Turbo Coding (DB-CTC)◈Low-Density Parity Check Coding (LDPC) ◈Shortened block turbo codes (SBTC)
39::: ETRI, The Future Wave ::: 디지털방송연구단
Spectrum Sensing
▣ Proposed methods still remain to be evaluated and compared (Tiger Team)
▣ Several techniques were introduced at previous meetings and have been included in the PHY spec in section 8.8◈Energy detection (full bandwidth or pilot)◈Multi-resolution spectrum sensing and Analog auto correlation◈PN511 or PN63 sequence detection◈Segment sync detector◈Cyclostationary feature detection◈Spectral correlation◈Optimal radiometer
▣ Primary waveforms are DTV and analog FM for wireless microphones◈802.22 TG1 beacon in MAC Section 6.21.1.7.x◈More on this later
40::: ETRI, The Future Wave ::: 디지털방송연구단
Multiple Antenna Options
▣ The following options are under consideration (Sec. 8.10)◈Downlink Closed Loop SDMA◈Adaptive Beam-Forming Techniques◈Space Time Block Coding (STBC)◈Combined Diversity/Spatial multiplexing/Delay
Management
41::: ETRI, The Future Wave ::: 디지털방송연구단
Reference Architecture
Convergence Sublayer / Bridge (e.g., 802.1d)
MAC
PHY
...MAC
PHY
MAC
PHY
Spectrum Manager
Higher Layers: IP, ATM, 1394, etc.
PHY/MAC 1 PHY/MAC 2 PHY/MAC n
Spectrum Manager– facilitates use of non-contiguous channels (channel aggregation)– responsible for maintaining global view of target RF spectrum– assigns spectrum to MAC/PHY modules
42::: ETRI, The Future Wave ::: 디지털방송연구단
Superframe n-1 Superframe n Superframe n+1 ...Time
...
Preamble SCH frame 0 frame 1 frame m...
TV Channelt-1
TV Channelt
TV Channelt+1
Time
Preamble SCH
Preamble SCH
Fre
qu
en
cy
Preamble SCH Frame0
Frame1
Framem-2
(Quiet)...
... Frame0
Frame1
Preamble SCH
Preamble SCH
Occupied by Incumbent
Occupied by Incumbent
Framen
Occupied by Incumbent
Framem
Framem-1
Superframe Structure
Superframe Control Header (SCH)
• TV channels being bonded• Quiet period schedule• Coexistence and superframe information
• Number and size of frames• Information on periodic quiet periods• ID an transmit power of transmitter
•Location configuration information
43::: ETRI, The Future Wave ::: 디지털방송연구단
Protocol Stack Architecture (cont.)
▣ Flexible and scalable channel assignment◈ Implementers decide on the algorithm
44::: ETRI, The Future Wave ::: 디지털방송연구단
MAC View of Frame
frame n-1 frame n frame n+1 ...Time
...
DS PHY PDU
Preamble FCH DS burst 1 DS burst 2 DS burst x...
BcastMsgs
MACPDUs
MAC PDU 1 ... MAC PDU y Pad
MACHeader MAC Payload CRC
DS subframe
Initializationslots
BW requestslots
US PHY PDU(CPE m)
US PHY PDU(CPE p)
...
US subframe
Preamble US burst
MAC PDU 1 ... MAC PDU k Pad
MACHeader MAC Payload CRC
Sliding self-coexistence
slots
Can appear ineither DS or US
BCH
UCSNotification
Slots
PDU – protocol data unit
CRC – cyclic redundancy check
Header – PDU length, connection ID, encryption
45::: ETRI, The Future Wave ::: 디지털방송연구단
Ranging
▣ Downstream management◈ If CPE CINR falls below the range required for the
specified burst profile, the CPE requests transition to a new burst profile
◈See section 6.17.1▣ Upstream management
◈Consists of two procedures:– Initial ranging allows a CPE to join a network and
acquire correct Tx parameters– Periodic ranging allows the CPE to maintain upstream
communications◈For periodic ranging, timers must be maintained for each
channel in DFH operation◈The algorithm is described in section 6.17.2
46::: ETRI, The Future Wave ::: 디지털방송연구단
Distributed Quiet Period▣ When multiple CPEs are operating on different aggregate channels, a hidden node
can result if the CPEs only sense on their active channel▣ Meanwhile the BS is broadcasting on all aggregated channels and interference to
the incumbent results
47::: ETRI, The Future Wave ::: 디지털방송연구단
Distributed Quiet Period▣ This situation can be remedied by distributing the quiet period▣ Each channel is interrupted only once using DQP, while
simultaneous QP would require 3x interruption in this example
49::: ETRI, The Future Wave ::: 디지털방송연구단
Channel Set
▣ Channel Set: Definitions- Active set 1: a set of used channels for a certain CPE - Active set 2: a set of used channels for a certain BS- Candidate set: a set of clean channels available for a certain CPE
and BS- Occupied set: a set of occupied channels by incumbent user
which a certain CPE finds - Disallowed Set: a set of channels whose access are not allowed
by regulation- Null set : a set of channels that are not classified as one of above
five sets
* Note: The allowed set is defined by union of candidate set and null set depending on channel’s SIR level
50::: ETRI, The Future Wave ::: 디지털방송연구단
Channel Set (cont.)§ Transition diagram for channel set① The channel in null, active or candidate set
becomes a member of occupied set as incumbent user appears.
② Incumbent service releases the channel and its quality is better than an existing member of the candidate set, then it is classified as a member of candidate set.
③ Incumbent service releases the channel and its quality is worse than all member of the candidate set, then it is classified as a member of null set.
④ If the channel quality is better than an existing member of the candidate set, then it replaces the member of candidate set.
⑤ The channel becomes active by new allocation to a WRAN service.
⑥ The poorest channel in candidate set goes to a member of null set as its quality is worse than a new member of candidate set, which comes from null(4), active(7) or occupied(2) sets
⑦ The channel is released due to the termination of its usage and its quality is better than an existing member of the candidate set.
⑧ The channel is classified as a member of null set as the WRAN service releases the channel and its quality is worse than all member of the candidate set.
Null Set
Active Set
Occupied SetCandidate Set1
1
2
75
8
46 13
51::: ETRI, The Future Wave ::: 디지털방송연구단
Sensing Receiver Architecture
MAC
Fine/Feature
RFE
Energy Detection
Omni Antenna
Control
52::: ETRI, The Future Wave ::: 디지털방송연구단
Spectrum Sensing Strategy
Energy Detectionfor wide band
(Analog, RSSI, MRSS, FFT… )
Begin Sensing
Fine/Feature Detection for single channel
End Sensing
occupied?Y
N
MAC(Select
single channel)
FFT CSFDField Sync
OptimumRadiometer
Multi-cycleDetector
AACSpectral
Correlation
Spectrum Usage
Database(BS) ATSC
Segment Sync
53::: ETRI, The Future Wave ::: 디지털방송연구단
향후 일정
Closing
Final Approval/Publication
Submittal to RevCom
Sponsor ballot
WG Draft Standard Process Start
Consolidation/Selection
Functional Requirements 확정 및 Call for ProposalsProposals/Contributions
Editing of Functional Requirements
Editing of Functional Requirements
Editing of Functional Requirements
Draft Functional Requirements
IEEE 802.22 Kick-off meetingWorking Group policy and procedures
주요내용
Denver
Hawaii
Vancouver
Garden Grove, CA
San Francisco
비고
2007. 6.
2008. 12.
2008. 1.
2007. 1.
Interim2006. 1.
Plenary2005. 11.
Interim2005. 9.
Plenary2005. 7.
Interim2005. 5.
Plenary2005. 3
Interim2005. 1.
Plenary2004. 11.
회의종류날짜
IEEE 802.22 표준화 일정IEEE 802.22 IEEE 802.22 표준화표준화 일정일정