120MHz channelization solution Month Year doc.: IEEE 802.11-yy/xxxxr0 Nov. 2010 120MHz channelization solution Date: 2010-11-10 Authors: LvKaiying, ZTE Corporation John Doe, Some Company

Month Year doc.: IEEE 802.11-yy/xxxxr0 Nov. 2010 Abstract Current specification support an efficient channelization in China’s (5,725 ~ 5,850 MHz) spectrum but lack of detailed design Three 120MHz channelization and operation solutions are proposed in this contribution Straw Polls LvKaiying, ZTE Corporation John Doe, Some Company

Nov. 2010 Background . In last Hawaii meeting, following statements were accepted: In R3.1.E: The draft specification shall include support for an efficient channelization in China’s (5,725 ~ 5,850 MHz) spectrum. The following straw poll is accepted but missed in current spec frame: “The total bandwidth of the channels defined for China shall be equal to or not less than 120 MHz” In China, there’re no many 11n or 11a devices in the market working on 5GHz currently. But before end of 2012, the devices quantity is not predictable. LvKaiying, ZTE Corporation

120MHz Channelization Approaches Nov. 2010 120MHz Channelization Approaches Approach 1 Shifted 20MHz, 40MHz, and 80MHz channels and one optional 120MHz channel 7.5MHz left shifted center frequency allows six 20 MHz channels and three 40 MHz channels No change to current 20MHz, 40MHz and 80MHz signal design Need to define a new 120MHz signal, which could allow a combination of current channels or a complete 120MHz channel signal. Approach2 Non-shifted 20MHz, 40 MHz and 80 MHz channels as current 20MHz, 40MHz and 80MHz design One optional 120MHz channel LvKaiying, ZTE Corporation

Channelization Approach 1 Nov. 2010 Channelization Approach 1 7.5MHz 5735 40MHz 80MHz 20MHz 5727.5 5847.5 f MHz 120MHz 5835 12.5MHz Legacy mode Enhanced mode LvKaiying, ZTE Corporation

Solution A based on channelization approach 1 Nov. 2010 Solution A based on channelization approach 1 802.11ac AP starts a BSS alternatively operating on shifted and non-shifted channels in time domain, with two primary channels defined for shifted channel set and non-shifted channel set. 802.11ac AP alternatively sends beacons and other control & management frames on shifted and non-shifted channels in time domain. Legacy STAs access and associate with 802.11ac AP in non-shifted channels. 802.11ac STAs can access and associate with 802.11ac AP in either shifted or non–shifted channels. CFP/CP window parameters are configured to guarantee no time confliction between transmission on two channel sets. LvKaiying, ZTE Corporation

Solution A based on channelization approach 1 Nov. 2010 Solution A based on channelization approach 1 LvKaiying, ZTE Corporation

Solution A Analysis Coexistence Backward compatibility Nov. 2010 Solution A Analysis Coexistence OBSS scanning before and after BSS establishment AP Alternatively scans OBSS in shifted and non-shifted channels to detect OBSS overlapping. STAs perform OBSS scanning in shifted and non-shifted channels and report to AP AP may shift to other channels to avoid interference to the existing OBSS. Backward compatibility The legacy mode (non-shifted channelization) can be used to support legacy devices. 120MHz Transmission (optional) The enhanced mode (shifted channelization) can provide 120MHz data transmission when all 6 20MHz channels are idle. LvKaiying, ZTE Corporation

Challenges to Solution A Nov. 2010 Challenges to Solution A Regulatory extension for 5.7GHz for Chinese spectrum. 120MHz channel definition with New preamble design New pilot design New sub-carrier sequence design RF front-end implementation design Interference control Complex OBSS scanning for overlapped & non-orthogonal channels LvKaiying, ZTE Corporation

Channelization Approach 2 Nov. 2010 Channelization Approach 2 7.5 5735 40MHz 80MHz 20MHz 5727.5 5847.5 f MHz 120MHz 5835 12.5 Legacy mode 120MHz mode LvKaiying, ZTE Corporation

Channelization Approach 2 Nov. 2010 Channelization Approach 2 Current design for 20/40/80MHz transmission New 120MHz design for potential 120MHz channel for data-only transmission 120MHz data transmission is available only when five non-shifted 20 MHz channels are detected as idle by both initiator and responder Quintuplicate RTSs/CTSs are transmitted in five non-shifted 20 MHz channels to reserve 120MHz channel Quintuplicate ACKs are transmitted in five 20 MHz channels Possible methods for 120MHz data transmission detection by preamble detecting on five 20MHz channels [preferred] by 120MHz bandwidth information indicated in RTS/CTS frame by explicitly phased division to indicate 120MHz transmission LvKaiying, ZTE Corporation

Channelization Approach 2 Nov. 2010 Channelization Approach 2 LvKaiying, ZTE Corporation

Solution B based on channelization approach 2 Nov. 2010 Solution B based on channelization approach 2 Basically burst-style time division of legacy transaction period and 120MHz data only transmission period Only data frames and some management frames transmitted with 120MHz bandwidth; Control frames and most networking joining related management frames transmitted with current channels. LvKaiying, ZTE Corporation

Solution C based on channelization approach 2 Nov. 2010 Solution C based on channelization approach 2 Allow phased division of legacy transaction period and 120MHz data only transmission period AP controlled or STA requested phased division of legacy transaction period and120MHz data only transmission period CCA detection on 5 non-shifted 20MHz channels. If all 5 channels are idle, then AP sends CTS-to-self on 5 non-shifted 20MHz channels to reserve 100MHz channel After120MHz transaction phase starts, AP and 120MHz recipient STAs exchange RTS/CTS on 5 legacy 20MHz channels to avoid OBSS interference LvKaiying, ZTE Corporation

Challenges to channelization approach 2 Nov. 2010 Challenges to channelization approach 2 120MHz channel definition with New preamble design New pilot design New sub-carrier sequence design RF front-end implementation design RTS detection by preamble detection on five 20MHz channels LvKaiying, ZTE Corporation

Nov. 2010 Strawpoll #1 Do you support adding the following text into the specification framework document, 15-09/0992? "when 120MHz bandwidth is implemented, e.g. in China, an 11ac device shall support a shifted 20/40/80MHz channelization and a possible 120MHz channelization.” Yes: No: Abstain: LvKaiying, ZTE Corporation

Nov. 2010 Strawpoll #2 Do you support adding the following text into the specification framework document, 15-09/0992? “when 120MHz bandwidth is implemented, e.g. in China, an 11ac device shall support a non-shifted 20/40/80MHz channelization and a possible shifted120MHz channelization.” Yes: No: Abstain: LvKaiying, ZTE Corporation

Nov. 2010 Strawpoll #3 Do you support adding the following text into the specification framework document, 15-09/0992? “To provide co-existence among 11ac devices and 11n/11a devices when 120MHz bandwidth is implemented, e.g. in China, a 802.11ac AP shall starts a BSS alternatively operating on shifted and non-shifted channels in time domain.” Yes: No: Abstain: LvKaiying, ZTE Corporation

Nov. 2010 Strawpoll #4 Do you support adding the following text into the specification framework document, 15-09/0992? “when 120MHz bandwidth is implemented, e.g. in China, a 11ac STA could transmit a data frame using a 120MHz signal.” Yes: No: Abstain: LvKaiying, ZTE Corporation

Nov. 2010 Thank you! LvKaiying, ZTE Corporation