doc.: IEEE /0057r0January 2016 SubmissionSlide 1 Indication for UL MU Carrier Sensing Date: Kiseon Ryu et al. (LG) Authors: NameAffiliationAddressPhone Kiseon Ryu LG Electronics 19, Yangjae-daero 11gil, Seocho-gu, Seoul , Korea Jinyoung Chun Jeongki Kim Suhwook Kim JayH Park Jinsoo Choi Eunsung Park Dongguk Lim Jinmin Kim HanGyu Cho

Intel Corporation. All rights reserved. 2 Intel Labs Wireless Communication Lab, Intel Labs 2 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 Slide 2 Authors (continued) NameAffiliationAddressPhone Hongyuan Zhang Marvell 5488 Marvell Lane, Santa Clara, CA, Yakun Sun Lei Wang Liwen Chu Jinjing Jiang Yan Zhang Rui Cao Sudhir Srinivasa Bo Yu Saga Tamhane Mao Yu Xiayu Zheng Christian Berger Niranjan Grandhe Hui-Ling Lou

Intel Corporation. All rights reserved. 3 Intel Labs Wireless Communication Lab, Intel Labs 3 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 Slide 3 Authors (continued) Robert Stacey Intel 2111 NE 25th Ave, Hillsboro OR 97124, USA Shahrnaz Azizi Po-Kai Huang Qinghua Li Xiaogang Chen Chitto Ghosh Laurent Cariou Yaron Alpert Assaf Gurevitz Ilan Sutskover NameAffiliation AddressPhone Ron Porat Broadcom Sriram Venkateswaran Matthew Fischer Leo Montreuil Andrew Blanksby Vinko Erceg

Intel Corporation. All rights reserved. 4 Intel Labs Wireless Communication Lab, Intel Labs 4 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 Slide 4 Authors (continued) NameAffiliationAddressPhone Alice Chen Qualcomm 5775 Morehouse Dr. San Diego, CA, USA Albert Van Zelst Straatweg 66-S Breukelen, 3621 BR Netherlands Alfred Asterjadhi 5775 Morehouse Dr. San Diego, CA, USA Arjun Bharadwaj 5775 Morehouse Dr. San Diego, CA, USA Bin Tian 5775 Morehouse Dr. San Diego, CA, USA Carlos Aldana 1700 Technology Drive San Jose, CA 95110, USA George Cherian 5775 Morehouse Dr. San Diego, CA, USA Gwendolyn Barriac 5775 Morehouse Dr. San Diego, CA, USA Hemanth Sampath 5775 Morehouse Dr. San Diego, CA, USA Lin Yang 5775 Morehouse Dr. San Diego, CA, USA Menzo Wentink Straatweg 66-S Breukelen, 3621 BR Netherlands Naveen Kakani 2100 Lakeside Boulevard Suite 475, Richardson TX 75082, USA Raja Banerjea 1060 Rincon Circle San Jose CA 95131, USA Richard Van Nee Straatweg 66-S Breukelen, 3621 BR Netherlands

Intel Corporation. All rights reserved. 5 Intel Labs Wireless Communication Lab, Intel Labs 5 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 Slide 5 Authors (continued) NameAffiliationAddressPhone Rolf De Vegt Qualcomm 1700 Technology Drive San Jose, CA 95110, USA Sameer Vermani 5775 Morehouse Dr. San Diego, CA, USA Simone Merlin 5775 Morehouse Dr. San Diego, CA, USA Tao Tian 5775 Morehouse Dr. San Diego, CA, USA Tevfik Yucek 1700 Technology Drive San Jose, CA 95110, USA VK Jones 1700 Technology Drive San Jose, CA 95110, USA Youhan Kim 1700 Technology Drive San Jose, CA 95110, USA Bo Sun ZTE #9 Wuxingduan, Xifeng Rd., Xi'an, China Kaiying Lv Yonggang Fang Ke Yao Weimin Xing Brian Hart Cisco Systems 170 W Tasman Dr, San Jose, CA Pooya Monajemi Thomas DerhamOrange

Intel Corporation. All rights reserved. 6 Intel Labs Wireless Communication Lab, Intel Labs 6 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 Slide 6 Authors (continued) Joonsuk Kim Apple Aon Mujtaba Guoqing Li Eric Wong Chris Hartman NameAffiliationAddressPhone James Yee Mediatek No. 1 Dusing 1 st Road, Hsinchu, Taiwan Alan Jauh Chingwa Hu m Frank Hsu Thomas Pare Mediatek USA 2860 Junction Ave, San Jose, CA 95134, USA ChaoChun Wang om James Wang Jianhan Liu Tianyu Wu Zhou Lan Russell Huang m

Intel Corporation. All rights reserved. 7 Intel Labs Wireless Communication Lab, Intel Labs 7 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 Slide 7 Authors (continued) NameAffiliationAddressPhone Peter Loc Huawei Le Liu F1-17, Huawei Base, Bantian, Shenzhen Jun Luo 5B-N8, No.2222 Xinjinqiao Road, Pudong, Shanghai Yi Luo F1-17, Huawei Base, Bantian, Shenzhen Yingpei Lin 5B-N8, No.2222 Xinjinqiao Road, Pudong, Shanghai Jiyong Pang 5B-N8, No.2222 Xinjinqiao Road, Pudong, Shanghai Zhigang Rong Telesis Court, Suite 365, San Diego, CA NA Rob Sun 303 Terry Fox, Suite 400 Kanata, Ottawa, Canada David X. Yang F1-17, Huawei Base, Bantian, Shenzhen Yunsong Yang Telesis Court, Suite 365, San Diego, CA NA Junghoon Suh 303 Terry Fox, Suite 400 Kanata, Ottawa, Canada Jiayin Zhang 5B-N8, No.2222 Xinjinqiao Road, Pudong, Shanghai Edward Au 303 Terry Fox, Suite 400 Kanata, Ottawa, Canada m Teyan Chen F1-17, Huawei Base, Bantian, Shenzhen Yunbo Li F1-17, Huawei Base, Bantian, Shenzhen

Intel Corporation. All rights reserved. 8 Intel Labs Wireless Communication Lab, Intel Labs 8 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 Slide 8 Authors (continued) NameAffiliationAddressPhone Fei Tong Samsung Innovation Park, Cambridge CB4 0DS (U.K.) Hyunjeong Kang Maetan 3-dong; Yongtong-Gu Suwon; South Korea Kaushik Josiam 1301, E. Lookout Dr, Richardson TX (972) Mark Rison Innovation Park, Cambridge CB4 0DS (U.K.) Rakesh Taori 1301, E. Lookout Dr, Richardson TX (972) Sanghyun Chang Maetan 3-dong; Yongtong-Gu Suwon; South Korea Yasushi Takatori NTT 1-1 Hikari-no-oka, Yokosuka, Kanagawa Japan Yasuhiko Inoue Shoko Shinohara Yusuke Asai Koichi Ishihara Junichi Iwatani Akira Yamada NTT DOCOMO 3-6, Hikarinooka, Yokosuka- shi, Kanagawa, , Japan Fujio Watanabe 3240 Hillview Ave, Palo Alto, CA com Haralabos Papadopoulos tions.com

Intel Corporation. All rights reserved. 9 Intel Labs Wireless Communication Lab, Intel Labs 9 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 Slide 9 Authors (continued) NameAffiliationAddressPhone Masahito Mori Sony Corp. Yusuke Tanaka m Yuichi Kazuyuki Sakoda om William

Intel Corporation. All rights reserved. 10 Intel Labs Wireless Communication Lab, Intel Labs 10 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 Background (1/2) Typical 11ax UL MU frame exchange sequences: Basic and Cascading The details of the 11ax UL MU frame exchange sequences are still TBD, e.g., what’re the CS rules (i.e., physical and virtual carrier sense) for STAs before responding to a Trigger frame? What’s the right IFS between a Trigger frame and a UL MU PPDU? This contribution provides a summary of the relevant discussion so as to bring this topic into conclusion. Kiseon Ryu et al. (LG) Slide 10 UL MU PPDUTrigger TXOP AP Gains the channel access DL ULDL ACK /BA UL MU PPDUTrigger + DL MU Data TXOP AP Gains the channel access DLULDL ACK /BA Basic: Trigger ++ UL MU data ++ DL ACK/BA Cascading: (Trigger + DL MU data) ++ UL MU data ++ DL ACK/BA

Intel Corporation. All rights reserved. 11 Intel Labs Wireless Communication Lab, Intel Labs 11 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 Background of (2/2) In the 11ax SFD [1] –A STA shall consider CCA status to respond to a Trigger frame under a non-null TBD set of conditions. The 11ax SFD text specifies two scenarios: –Scenario-1: Under a non-null TBD set of conditions, a STA can transmit UL MU PPDU in response to a Trigger frame, without considering carrier sense (CS); –Scenario-2: Otherwise, a STA shall consider carrier sense (CS) before transmitting UL MU PPDU in response to a Trigger frame This contribution will attempt to focus on the issue. –What is the non-null set of conditions for a STA not to consider CS before UL MU transmission in response to a Trigger Frame? Kiseon Ryu et al. (LG) Slide 11

Intel Corporation. All rights reserved. 12 Intel Labs Wireless Communication Lab, Intel Labs 12 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 What’re the conditions for not doing CS? (1/2) What is the possible non-null set of conditions for a STA not to consider CS before UL MU transmission in response to a Trigger frame? –Condition-1: Depending on the contents and the duration of the UL MU transmission: A STA is not required to consider CS before its UL transmission in response to a Trigger Frame, if the STA’s UL transmission contains ACK/BA and the duration of the UL MU transmission is below a TBD threshold. –Condition-2: Indication in the Trigger Frame: A STA is not required to consider CS before its UL transmission in response to a Trigger Frame, if the Trigger Frame carries an indication indicating no need for the STA to sense the channel before its UL transmissions in response to the Trigger Frame. –Condition-3: UL MU frame exchange sequence protected by RTS/CTS: A STA is not required to consider CS before its UL transmission in response to a Trigger Frame, if the STA knows that the UL MU frame exchange sequence is protected by RTS/CTS. –Condition-4: Multiple UL MU transmission in the same TXOP: A STA is not required to consider CS before its UL transmission in response to a Trigger Frame, if the STA has done the channel sensing previously on the same UL allocation, in the same TXOP with multiple UL MU frame exchange sequences. –Condition-others: Etc. Kiseon Ryu et al. (LG) Slide 12

Intel Corporation. All rights reserved. 13 Intel Labs Wireless Communication Lab, Intel Labs 13 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 What’re the conditions for not doing CS? (2/2) Discussions about the conditions list in previous slide: –Can the Condition-2 be used to cover the cases of the other three conditions? Yes, as the other three conditions can be viewed as examples of the criteria for AP to set up the CS indication. –Should we specify the criteria regarding how AP sets the CS indication in Condition-2? Could, to give some examples, but won’t be an exhausted list; but not necessary, as it belongs to implementation details, no impact on interoperability. –Then, Condition-2 only or all 4 conditions? Prefer to Conditon-2 only, for simplicity Kiseon Ryu et al. (LG) Slide 13 UL MU PPDUTrigger TXOP AP Gains the channel access DL ULDL ACK /BA Carrier Sense (CS) UL MU PPDUTrigger TXOP AP Gains the channel access DL ULDL ACK /BA No carrier sense (CS) CS-request indicator: On CS-request indicator: Off

Intel Corporation. All rights reserved. 14 Intel Labs Wireless Communication Lab, Intel Labs 14 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 Reference [1] ax-spec-framework Slide 14 LG Electronics

Intel Corporation. All rights reserved. 15 Intel Labs Wireless Communication Lab, Intel Labs 15 Intel Confidential Submission doc.: IEEE /0057r0 January 2016 Straw-poll Do you agree to change the SFD text in the clause 4.3 as below? –A STA shall consider CCA status to respond to a Trigger frame under a non-null TBD set of conditions. –Trigger frame carries an indication of whether or not the carrier sensing is required for the STA to transmit a UL MU PPDU in response to a Trigger frame. If a Trigger frame indicates that the carrier sensing is required, the STA shall consider the channel status of the physical channel sensing (ED) and virtual carrier sense (NAV) before UL MU transmission in response to the Trigger Frame. Otherwise, the STA may transmit a UL MU PPDU without the carrier sensing. The AP shall require the carrier sensing except under TBD conditions. Yes: No: Abstain: Kiseon Ryu et al. (LG) Slide 15