Submission doc.: IEEE /0617r0 Duration and MAC Padding for UL MU PPDUs Date: Authors: G. Ding et al, QualcommSlide 1 Gang Ding Qualcomm 5775 Morehouse Dr. San Diego, CA, Simone Merlin5775 Morehouse Dr. San Diego, CA, George Cherian5775 Morehouse Dr. San Diego, CA, USA Alfred Asterjadhi5775 Morehouse Dr. San Diego, CA, USA Gwendolyn Barriac5775 Morehouse Dr. San Diego, CA, USA Carlos Aldana1700 Technology Drive San Jose, CA 95110, USA Albert Van ZelstStraatweg 66-S Breukelen, 3621 BR Netherlands Bin Tian5775 Morehouse Dr. San Diego, CA, USA Hemanth Sampath5775 Morehouse Dr. San Diego, CA, USA Menzo WentinkStraatweg 66-S Breukelen, 3621 BR Netherlands Richard Van NeeStraatweg 66-S Breukelen, 3621 BR Netherlands Rolf De Vegt1700 Technology Drive San Jose, CA 95110, USA Sameer Vermani5775 Morehouse Dr. San Diego, CA, USA Tevfik Yucek 1700 Technology Drive San Jose, CA 95110, USA VK Jones1700 Technology Drive San Jose, CA 95110, USA Youhan Kim1700 Technology Drive San Jose, CA 95110, USA

Submission doc.: IEEE /0617r0 Slide 2 NameAffiliationAddressPhone Liwen Chu Marvell 5488 Marvell Lane, Santa Clara, CA, Lei Wang Jinjing Jiang Hongyuan Zhang Yakun Sun Yan Zhang Rui Cao Jie Huang Sudhir Srinivasa Saga Tamhane Mao Yu Edward Au Hui-Ling Lou G. Ding et al, Qualcomm Authors (continued)

Submission doc.: IEEE /0617r0 Slide 3 Authors (continued) G. Ding et al, Qualcomm NameAffiliationAddressPhone Wookbong Lee LG Electronics 19, Yangjae-daero 11gil, Seocho-gu, Seoul , Korea Kiseon Ryu Jinyoung Chun Jinsoo Choi Jeongki Kim Giwon Park Dongguk Lim Suhwook Kim Eunsung Park HanGyu Cho Laurent cariou Orange Thomas Derham

Submission doc.: IEEE /0617r0 Slide 4 Authors (continued) G. Ding et al, Qualcomm NameAffiliationAddressPhone Ron Porat Broadcom Matthew Fischer Sriram Venkateswaran Tu Nguyen Vinko Erceg Robert Stacey Intel 2111 NE 25th Ave, Hillsboro OR 97124, USA Eldad Perahia Shahrnaz Azizi Po-Kai Huang Qinghua Li Xiaogang Chen Chitto Ghosh Rongzhen Yang

Submission doc.: IEEE /0617r0 Slide 5 Authors (continued) G. Ding et al, Qualcomm 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 Yusuke Asai Koichi Ishihara Akira Kishida Akira Yamada NTT DOCOMO 3-6, Hikarinooka, Yokosuka- shi, Kanagawa, , Japan Fujio Watanabe 3240 Hillview Ave, Palo Alto, CA com Haralabos Papadopoulos tions.com

Submission doc.: IEEE /0617r0 Slide 6 Authors (continued) G. Ding et al, Qualcomm NameAffiliationAddressPhone Phillip Barber Huawei The Lone Star State, TX ch.com Peter Loc 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 Zhou Lan F1-17, Huawei Base, Bantian, SHenzhen Junghoon Suh 303 Terry Fox, Suite 400 Kanata, Ottawa, Canada Jiayin Zhang 5B-N8, No.2222 Xinjinqiao Road, Pudong, Shanghai

Submission doc.: IEEE /0617r0 Slide 7 Authors (continued) G. Ding et al, Qualcomm 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 Russell Huang m

Submission doc.: IEEE /0617r0 Slide 8 Authors (continued) G. Ding et al, Qualcomm NameAffiliationAddressPhone Brian Hart Cisco Systems 170 W Tasman Dr, San Jose, CA Pooya Monajemi Bo Sun ZTE #9 Wuxingduan, Xifeng Rd., Xi'an, China Kaiying Lv Yonggang Fang Ke Weimin Joonsuk Kim Apple Cupertino, CA Aon Mujtaba Guoqing Li Eric Wong Chris Hartman

Submission doc.: IEEE /0617r0 Introduction The TGax SFD [1] incudes initial specifications for the UL MU OFDMA/MIMO MAC protocol –An UL MU PPDU (MU-MIMO or OFDMA) is sent as an immediate response (IFS TBD) to a Trigger frame (format TBD) sent by the AP. [MAC Motion #3, March 2015] –The amendment shall include a mechanism to multiplex BA/ACK responses to DL MU transmission. –From [2]: This presentation discusses the duration of UL MU OFDMA PPDUs and the need for padding G. Ding et al, QualcommSlide 9

Submission doc.: IEEE /0617r0 Proposal for UL OFDMA The Trigger Frame indicates the duration of the UL OFDMA Each STA transmits an UL OFDMA PPDU of the duration indicated by the Trigger If a STA does not have enough data to fill the available PSDU bytes, then the MAC adds A-MPDU padding as defined in.11ac specifications for DL MU MIMO –While A-MPDU_length < PSDU_LENGTH and A-MPDU_Length mod 4 ≠ 0, add a subframe pad octect and increment A-MPDU_Length by 1. –While A-MPDU_length + 4 ≤ PSDU_LENGTH, add an A-MPDU EOF subframe and increment A-MPDU_Length by 4. (EOF subframe has Length field = 0 and EOF field = 1) –While A-MPDU_length < PSDU_LENGTH, add an EOF pad octet and increment A- MPDU_Length by 1 PPDU STA 2 TF Time duration PPDU STA1Pad Freq. BAs UL OFDMA G. Ding et al, QualcommSlide 10

Submission doc.: IEEE /0617r0 Motivations Each channel occupied by the UL OFDMA PPDU should be maintained busy for the time indicated by AP If a STA was allowed to end its transmission earlier, the unused sub-channel could be acquired by an OBSS STA, which may initiate a transmissions, potentially resulting in: –Interference with the following DL BAs Immediate BA not possible for STAs that terminated earlier –Corrupted reception of the remaining UL MU PPDUs due to interference at the AP –In particular, the primary channel should not be left unused while other STAs are completing the UL MU PPDU transmission on secondary channels The virtual protection provided by trigger frame (NAV) or UL MU PPDU PHY preamble (deferral for the PPDU duration) is not fully reliable against OBSS [3] Slide 11G. Ding et al, Qualcomm

Submission doc.: IEEE /0617r0 Conclusions For UL OFDMA we propose: –UL MU PPDUs from all the STAs shall end at the time duration indicated by AP –Same MAC padding rules as in 11ac DL MU MIMO can be used Slide 12G. Ding et al, Qualcomm

Submission doc.: IEEE /0617r0 Straw poll 1 Would you agree to add the following text to the SFD: –UL OFDMA PPDUs shall end at the time indicated in trigger frame, by adding padding if necessary Slide 13G. Ding et al, Qualcomm

Submission doc.: IEEE /0617r0 Straw poll 2 Would you agree to add the following text to the SFD: –The MAC padding for UL MU OFDMA PPDUs is done by using the 11ac A-MPDU padding procedure Slide 14G. Ding et al, Qualcomm

Submission doc.: IEEE /0617r0 References [1] ax-spec-framework.docx [2] ax-ul-mu-procedure.pptx [3] ax-obss-preamble-detection.ppt Slide 15G. Ding et al, Qualcomm