1. 80MHz/160MHz Protection Date: 2010-09-07 Authors: Date: September 2010
Feb, 2008
doc.: IEEE /xxxx
Date: September 2010
80MHz/160MHz Protection
Date:
Authors:
L. Chu et al
Liwen Chu, STMicroelectronics

2. HT TXOP Protection and Truncation
Date: September 2010
HT TXOP Protection and Truncation
802.11n introduces features that a legacy STAs can not understand: 40MHz transmission, frame aggregation, short GI etc.
40MHz non-HT duplicate mode is used to protect the 11n transmission:
Non-HT duplicate frames (e.g. RTS/CTS) are used to establish protection of its TXOP in two 20MHz channels, and
Non-HT duplicate CF-End frame are used to truncate the protect TXOP protected by non-HT duplicate frames.
To get a 40MHz EDCA based TXOP, a STA does EDCA backoff procedure in the primary channel, and detects the second channel being idle during PIFS interval before the TXOP.
FC HT-STA1
RTS
ch0
A-MPDU
(HT frame)
FC HT-AP1
ch0+ch1
RTS
ch1
CTS
ch0
BLKACK
11a-STA3
ch0+ch1
FC HT-AP1
11a-AP2
FC HT-STA1
11a-AP3
CTS
ch1
11a-STA2
ch1
ch0+ch1
ch0
11a –STA2
NAV
ch0
“ch0(primary channel)+ch1” is a 40MHz channel.
ch0 is a 20MHz channel.
11a –STA3
NAV
ch1
ch1 is a 20MHz channel.

3. 802.11ac TXOP Protection and Truncation
Date: September 2010
802.11ac TXOP Protection and Truncation
802.11ac uses 80/160 MHz channels.
802.11ac introduces new features that legacy a STAs and n STAs can not understand: DL-MU MIMO, new ac preamble etc.
802.11ac TXOP should be protected by frames which can be understood by a STAs and n STAs in each 20MHz channel.
80MHz/160MHz non-HT duplicate frames are used for such TXOP protection/truncation:
80MHz/160MHz non-HT duplicate frame duplicates 20 MHz non-HT transmission in each 20 MHz channel of a 80MHz/160MHz channel.
80MHz/160MHz Non-HT duplicate frames (e.g. RTS/CTS) are used to establish protection of its TXOP in four 20MHz channels or in eight 20MHz channels, and
80MHz/160MHz Non-HT duplicate CF-End frame is used to truncate the protect TXOP protected by non-HT duplicate frames in four 20MHz channels or in eight 20MHz channels.

4. 802.11ac TXOP Protection and Truncation (Cont’d)
Date: September 2010
802.11ac TXOP Protection and Truncation (Cont’d)
To get a 80MHz/160MHz EDCA based TXOP, a STA does EDCA backoff procedure in the primary channel, and detects the other 20MHz channels being idle during PIFS interval before the TXOP.
RTS
A-MPDU
(VHT frame)
ch3
RTS
ch2
ch0+ch1+ch2+ch3
RTS
ch1
VHT-AP1
RTS
ch0
VHT-STA1
CTS
ch0
ch1
ch2
ch3
BLKACK
FC HT-STA3
Ch0+ch1+ch2+ch3
VHT-STA1
VHT-AP1
11a-AP2
FC HT-AP3
11a-STA2
ch0+ch1
ch0+ch1+ch2+ch3
ch3
11a–STA2
NAV
ch3
“ch0(primary channel)+ch1+ch2+ch3” is a 80MHz channel.
“ch0(primary channel)+ch1” is a 40MHz channel.
FC HT–STA3
NAV
ch0
ch3 is a 20MHz channel.

5. 80MHz/160MHz non-HT Duplicate Transmission
Date: September 2010
80MHz/160MHz non-HT Duplicate Transmission
80MHz/160MHz Non-HT duplicate transmission is used to transmit to a, n STAs that nay be present in a 20MHz/40MHz channel covered by 80MHz/160MHz channel.
The L-STF, L-LTF and L-SIG shall be transmitted in the same way as in the ac 80MHz/160MHz VHT transmission.
The VHT-SIG, VHT-STF, VHT-LTF are not transmitted.

6. Date: September 2010
Straw Poll
Do you support adding the following item into the specification framework document, 11-09/0992?
R5.X: 80MHz/160MHz duplicate mode shall be included in the specification to protect 80MHz/160MHz transmission.