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Summary• This document proposes the PHY and MAC layer design for 802.11ad
operating in the 60GHz band
• PHY layer design– A hybrid PHY designed consisting of the SC PHY and the OFDM PHY is
proposed
– Channelization of the 60GHz band is presented
– Data rate modes of respective PHYs are listed
– Common mode signaling bridging across two PHYs is introduced
– Frame format for respective PHYs are presented
• MAC layer design– Proposed MAC contains Basic MAC and Enhanced MAC
– Basic MAC is based on 802.11-2007 supporting for 802.11 user experience
– Enhanced MAC purposes to achieve very high throughput (>1Gbps), support directivity, and coexist with other 60GHz systems and for QoS improvement
• Beamforming
May 2010
Hiroshi Harada, NICTSlide 2
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Motivation of Proposal
• This proposal has the following purposes of– Enhancement of 802.11 PHY and MAC to fulfill the
requirements of 802.11ad system
– Co-existence of other already standardized 60GHz systems such as 802.15.3c WPAN
May 2010
Hiroshi Harada, NICTSlide 3
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Presentation Outline
Section 1: PHY Proposal for 802.11ad– Overview of the Proposed 802.11ad PHY
– Channelization
– Modulation and Coding
– Common Mode Signaling
– SC PHY Frame Format
– OFDM PHY Frame Format
– PHY Simulation Results
Section 2: MAC Proposal for 802.11ad– Overview of the proposed 802.11ad MAC
– Enhanced MAC
– Co-existence
– MAC Simulation Results
May 2010
Hiroshi Harada, NICTSlide 4
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Section 1: PHY Proposal for 802.11ad
5
May 2010
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Abbreviations
• FEC – forward error correction
• MCS – Modulation and Coding Scheme
• SC - Single carrier
• OFDM - Orthogonal Frequency Division Multiplexing
• CMS – Common Mode Signaling
May 2010
Hiroshi Harada, NICTSlide 6
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Presentation Outline (PHY Layer)
• Overview of the Proposed 802.11ad PHY
• Channelization
• Modulation and Coding
• Common Mode Signaling
• SC PHY Frame Format
• OFDM PHY Frame Format
May 2010
Hiroshi Harada, NICTSlide 7
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Overview of the Proposed 802.11ad PHY
• The proposed 802.11ad PHY consists any or the combination of the following:– SC PHY
– OFDM PHY
• Features of the PHY modes:– The SC PHY mainly targets applications with low complexity
– The OFDM PHY mainly targets applications that require higher data rates
• To reduce implementation burden, both PHYs are designed to have similarities in the aspects of frame construction
• To manage multi-PHY-mode management and mitigate interference, the CMS is specified to facilitate coexistence between the SC PHY and the OFDM PHY
May 2010
Hiroshi Harada, NICTSlide 8
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Channelization
May 2010
Hiroshi Harada, NICTSlide 9
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Overview on SC and OFDM Data Rates
• The SC and OFDM classes of data rates give flexibility to various potential applications requiring data rate support from several hundreds of Mbps to several Gbps
• The data rate classes are categorized as:– Class 1 – up to 1.6Gbps
– Class 2 – up to 3Gbps
– Class 3 – up to 7 Gbps
• A Robust MCS called CMS is proposed to bridge between the SC and OFDM PHYs
• In OFDM PHY, three modes with different FFT sizes are proposed for flexibility.
May 2010
Hiroshi Harada, NICTSlide 10
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Timing Related Values for SC PHY
May 2010
Hiroshi Harada, NICTSlide 11
doc.: IEEE 802.11-10-0498-00-00ad
Submission
MCSs for SC PHY
May 2010
Hiroshi Harada, NICTSlide 12*Mandatory MCSs
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Timing Related Values for OFDM PHY MODE 1
May 2010
Hiroshi Harada, NICTSlide 13
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Timing Related Values for OFDM PHY MODE 2
May 2010
Hiroshi Harada, NICTSlide 14
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Timing Related Values for OFDM PHY MODE 3
May 2010
Hiroshi Harada, NICTSlide 15
doc.: IEEE 802.11-10-0498-00-00ad
Submission
MCS for OFDM PHY
May 2010
Hiroshi Harada, NICTSlide 16
*FFT size: 512, 128, 64
Data rates are for FFT sizes 512 and 128. For 64, data rates are around 10% less.
doc.: IEEE 802.11-10-0498-00-00ad
Submission
MCS for Common Mode Signaling
May 2010
Hiroshi Harada, NICTSlide 17
*Note that CMS is the first MCS in the SC PHY table
doc.: IEEE 802.11-10-0498-00-00ad
Submission
CMS Functional Description
• CMS is the most robust and long reaching MCS in the SC PHY and is specified to bridge between the SC PHY and OFDM PHY
• CMS is the mandatory MCS for all STAs
• CMS is employed in procedures facilitating multi-PHY-mode network management (i.e. discovery and synchronization) and other cross-PHY procedures
May 2010
Hiroshi Harada, NICTSlide 18
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Generic Frame Format• The following slides show the components of the SC PHY
and OFDM PHY frames– PLCP preamble
– SIGNAL
– DATA
• The modulation and coding schemes used in respective components are given
• The generic frame format for SC PHY and OFDM PHY are the same– PLCP preamble structure for SC PHY and OFDM PHY are the
same
– SIGNAL field structure for SC PHY and OFDM PHY are the same
• VA-MSDU allows– maximum length of each MSDU (including SFCS) : 1Mbytes – maximum length of aggregated MSDUs : 16Mbytes– Bi-directional VA-MSDU by using both of aggregation and aggregation ACK bitmap
44
Preamble PLCP Header PSDU Tail / Pad bits
MAC Header Frame Body FCS
MAC Header MAC Subheader HCS MSDU 1 SFCS MSDU 2 SFCSMSDU
16SFCS...
MAC HeaderMAC Subheader
With A-ACK bitmapHCS
MAC Header MSDU 1 SFCS MSDU 2 SFCSMSDU
16SFCS...
MAC SubheaderWith A-ACK bitmap
HCS
PHY frame
Normal MAC frame
VA-MADU MAC frame
VA-MADU ACK frame
Bi-directional VA-MADU with ACK
SFCS (Subframe FCS)
May 2010
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Negotiation for Aggregation• Negotiation for Aggregation
– are performed for capability confirmation– can be operated in CFP or CP– are performed on-demand between Src and Dest– are performed directly between AP and STAs– are performed directly between STA and STA after Directed Link Setup
(DLS) defined in 802.11-2007
45
Neg.
Neg.
DLS
Neg. Case 1 : communication between AP and STAs
Neg. Case 2 : communication between STA and STA
Hiroshi Harada, NICT
May 2010
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Directivity Support
• Directivity support for 802.11ad system includes directional association and beamforming
• Directional association– Directional beacons (up to 4 beacons) and Directional contention
periods (CPs) enable STAs to associate to AP directionally
• Beamforming– Beamforming protocol is based on 11/496r0
– broadcasts beacons to the supported directions– determines the directional beacon interval appropriately
• STAs – scan beacons on the supported directions– associate with AP on the directional CP
47
AP STAs
D-Beacon 1
D-Beacon 2
D-Beacon n
Detect Beacon
D-Beacon 3
Directional CP
Association
May 2010
Hiroshi Harada, NICT
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Enhanced Co-existence (1/4)- Co-existence for homogeneous systems -
• Enhanced co-existence provides co-existence among homogeneous systems and among heterogeneous systems
• Co-existence for homogeneous systems provides QoS assurance during CFP– Avoid mutual interference by overlapping homogenous
networks to data transmission during CFP
48
STAA
STAB
STAA Areain BSS A
STAB Areain BSS B
AP ofBSS B
AP ofBSS A
Mutualinterference
BCFP for STA A
CPBSS A
BCFP for STA B
CPBSS B
Mutual interference
May 2010
Hiroshi Harada, NICT
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Enhanced Co-existence (2/4)- Co-existence for homogeneous systems -
• Co-existence action frame (CAF) supports to avoid mutual interference by overlapping homogenous networks to data transmission during CFP
– CAF includes schedule information of CFP
– STAs periodically sends out CAFs for potentially incoming homogeneous networks
– STAs scan CAFs before transmitting data during CFP
May 2010
Hiroshi Harada, NICTSlide 49
STAA
STAB
STAA Areain BSS A
STAB Areain BSS B
CAFAP ofBSS B
AP ofBSS A
BCFP for STA A
CPBSS A
STA_B inBSS B
CAF
SCAN
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Enhanced Co-existence (3/4)- Co-existence for heterogeneous systems -
• There are two 60GHz unlicensed wireless system specifications in the IEEE 802 (802.15.3c and 802.11ad)
• A mechanism is proposed to facilitate coexistence between 802.15.3c and 802.11ad while minimizing the additional complexity in implementation
• The co-existence mechanism is based on the document 10/0231r3 (John R. Barr) and 10/0485r0(Chin-Sean Sum )
May 2010
Hiroshi Harada, NICTSlide 50
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Enhanced Co-existence (4/4)- Co-existence for heterogeneous systems -
• To detect other 60GHz systems operating in the same channels, the BSSs in the vicinity have a quiet period to create a clear channel
• The quiet periods scheduled by different BSSs partially align to avoid the detection of other systems from being interfered by the signal from adjacent BSS.
May 2010
Slide 51
BSS1
BSS3
BSS2
B B BBSS1 Quiet Quiet
B B BBSS2 Quiet Quiet
B B BBSS3 Quiet Quiet
DS
BBeacon
Quiet Quiet period
Quiet
Quiet
Quiet
AP1 requests AP2 and AP3 to align their quiet periods for interference detection
1. All traffics are transmitted during CFP2. Priority based CFP allocation
3. CFP allocation for traffics is done by Req./Res. during CP based on EDCA
4. Uncompressed and lightly compressed videos • CFPs for those traffics are periodically allocated
5. Hard disk, local file transfer and Web-browing• CFPs for those traffics are terminated at the end of each CFP for traffics
6. Beamforming may have been performed during the beamforming period before data transmission in CFP
53
Priority Traffic
High Uncompressed video and lightly compressed video
Middle Hard disk and local file transfer
Low Web browsing
May 2010
Hiroshi Harada, NICT
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Simulation Parameters
54
Used MCSs
SC-MCS 3 1650Mbps BPSK/RS
SC-MCS 12 5280Mbps 16QAM/LDPC
Used ACK policies
No-ACK Immediate-ACK Aggregation-ACK (A-ACK)
Aggregation
Number of Subframes 8 subframes
Length of Subframe 8KB, 128KB, 1MB
IFS
MIFS 0.5us
SIFS 2.5us
BF period 0us
Simulation Time
10 minutes
Human blockage interval
-
CFP and CP timing
CFP = 9ms Beacon + CP = 1ms
May 2010
Hiroshi Harada, NICT
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Part3-1: MAC Performance for Home Living Room
55
May 2010
Hiroshi Harada, NICT
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Examples of Data Transmission in Home Living Room
56
• Peer-to-Peer Communication
• Video data is transmitted during CFP
May 2010
Hiroshi Harada, NICT
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Result for Home living Room
Goodput (>1Gbps) Delay (10ms) Packet Loss
SC-MCS 12 (5280Mbps,16QAM/LDPC)
No-ACK 2.98Gbps 7.0ms 0%
Imm-ACK 2.47Gbps 11.7ms 17%
A-ACK (8KB) 2.98Gbps 6.2ms 0%
A-ACK(128KB) 2.98Gbps 5.6ms 0%
May 2010
Hiroshi Harada, NICTSlide 57
• MCS 12 with No-ACK and MCS 12 with Aggregation ACKs (A-ACKs) can clear the requirements of goodput (>1Gbps), delay (<10ms) and packet loss rate (1e-8) in home living room
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Part3-2: MAC Performance for Office Conference Room
58
May 2010
Hiroshi Harada, NICT
doc.: IEEE 802.11-10-0498-00-00ad
Submission
May 2010
Hiroshi Harada, NICTSlide 59
4.5 m
3.0 m
door
window
STA 1
STA 2
STA 3
STA 4
STA 5
STA 6
STA 7
STA 8
AP (in ceiling)
x
y
00
COMPRESSED_VIDEO・ 2 to 1
FTP( file transfer )・ 9 to 2・ 3 to 5・ 4 to 9・ 5 to 3・ 7 to 8・ 9 to 7
HTTP・ 3・ 4・ 5・ 6
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Examples of Data Transmission in Office Conference Room
• Number of traffics during CFP– 1 Lightly Compressed Video traffic
– 7 FTP traffics
– 4 HTTP traffics
60
May 2010
Hiroshi Harada, NICT
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Result for Office Conference RoomThis result shows the performance of FTP and HTTP traffic when the
video traffic is satisfied the requirements of goodput (600Mbps) and delay (<10ms) on SC-MCS3
61
Goodput Delay (10ms)
Packet Loss
SC-MCS 3 (1650Mbps, BPSK/RS)
Video traffic
No-ACK 0.6Gbps 1.43ms 0%
Imm-ACK 0.6Gbps 1.26ms 0%
A-ACK (8KB) 0.6Gbps 1.48ms 0%
FTP traffic
No-ACK 51.3Mbps - 0%
Imm-ACK 12.2Mbps - 0%
A-ACK (8KB) 51.3Mbps - 0%
HTTP traffic
No-ACK 0.878Mbps 0.611s 0%
Imm-ACK 0.762Mbps 0.705s 0%
A-ACK (8KB) 0.870Mbps 0.593s 0%
May 2010
Hiroshi Harada, NICT
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Conclusion• This document proposes the PHY and MAC layer design for 802.11ad
operating in the 60GHz band
• PHY layer design– A hybrid PHY designed consisting of the SC PHY and the OFDM PHY is
proposed– Channelization of the 60GHz band is presented– Data rate modes of respective PHYs are listed– Common Mode Signaling bridging across two PHYs is introduced– Frame format for respective PHYs are presented
• MAC layer design– Proposed MAC contains Basic MAC and Enhanced MAC– Basic MAC is based on 802.11-2007 supporting for 802.11 user experience– Enhanced MAC purposes to achieve very high throughput (>1Gbps),
support directivity, and coexist other 60GHz systems and for QoS improvement
May 2010
Hiroshi Harada, NICTSlide 62
doc.: IEEE 802.11-10-0498-00-00ad
Submission
Strawpoll
• “Do you support adopting the whole or part of the complete proposal in 10/0498r0 as the material to create the first draft of the TGad amendment?”– Yes, No, Abstain