1. doc.: IEEE 802.11-12/0830r0 Submission July 2012 Yongho Seok, LG ElectronicsSlide 1 NDP Probing Date: 2012-07-12 Authors: NameAffiliationsAddressPhoneEmail Yongho SeokLG Electronics LG R&D Complex Anyang-Shi, Kyungki- Do, Korea +82-31-450-1947yongho.seok@lge.com Jinsoo ChoiLG Electronics Jeongki KimLG Electronics Jin Sam KwakLG Electronics Eric WongBroadcomSunnyvale, CA+1 408 922 6672ewong@broadcom.com Matthew FischerBroadcommfischer@broadcom.com Minyoung ParkIntelHillsboro, OR+1 503 712 4705minyoung.park@intel.com Adrian StephensIntel Tom TetzlaffIntel Emily QiIntel Simone MerlinQualcommSan Diego, CA+1 858 845 1243smerlin@qualcomm.com Santosh AbrahamQualcomm Menzo WentinkQualcomm Alfred AsterjadhiQualcomm Amin JafarianQualcomm Hemanth SampathQualcomm VK jonesQualcomm

2. doc.: IEEE 802.11-12/0830r0 SubmissionSlide 2 NameAffiliationsAddressPhoneEmail Yong LiuMarvell Hongyuan ZhangMarvell Sudhir SrinivasaMarvell George CalcevHuaweiRolling Meadows, IL, USA George.Calcev@huawei.co m Osama Aboul MagdHuawei Young HoonHuawei Betty ZhaoHuawei David YangxunHuawei Bin ZhenHuawei ChaoChun WangMediaTek James WangMediaTek Jianhan LiuMediaTek Vish PonnampalamMediaTek James YeeMediaTek Huai-Rong Shao Samsung Electronics Chiu NgoSamsung Electronics Minho CheongETRI Jae Seung LeeETRI Hyoungjin KwonETRI Heejung YuETRI Sok-kyu LeeETRI Sun, Bo ZTE Lv, Kaiying ZTE Authors: July 2012

3. doc.: IEEE 802.11-12/0830r0 SubmissionYongho Seok, LG ElectronicsSlide 3 Authors: NameAffiliationsAddressPhoneEmail Sayantan ChoudhuryNokia Taejoon KimNokia Klaus DopplerNokia Chittabrata GhoshNokia Esa TuomaalaNokia Ken MoriPanasonic Rojan ChitrakarPanasonic Haiguang WangI2R Shoukang ZhengI2R Yeow Wai LeongI2R Zander LeiI2R Jaya ShankarI2R Anh Tuan HoangI2R Joseph Teo Chee MingI2R July 2012

4. doc.: IEEE 802.11-12/0830r0 Submission How much power does STA consume during the scanning? –In US [1], the numbers of 1MHz are 26 Total Energy Consumption = {(1360us*TX Power)+(550us*RX Power)}*26 = {(1360us*500mW)+(550us*250mW)}*26 = (0.68+0.1375)*26 = 21.255 mWxSec July 2012 Yongho Seok, LG ElectronicsSlide 4 Motivation

5. doc.: IEEE 802.11-12/0830r0 Submission July 2012 Yongho Seok, LG ElectronicsSlide 5 Motivation How much power does STA consume during the scanning? CWminMinChannelTime (TU) Energy Consumption 81= {(1360us * 500mW) + (1000us * 250mW) } * 26 = (0.68 + 0.25) * 26 = 24.18 mWxSec 322= (1360us * 500mW) + (2000us * 250mW) = (0.68 + 0.5) * 26 = 30.68 mWxSec

6. doc.: IEEE 802.11-12/0830r0 Submission July 2012 Yongho Seok, LG ElectronicsSlide 6 Motivation Standby time of the current smart phone having 1,500mAh battery is almost 350 hour. The average energy consumption per minute is 0.266mWh. –It assumes turning off Wi-Fi. What does Wi-Fi impact on the standby time ? –The Wi-Fi scanning frequency in the android OS is once per 20 second. –The Wi-Fi energy consumption per minute is 0.025mWh (30.7mWs*3/3600). –Wi-Fi is occupying about 9.3% compared with all components of the smart phone (e.g., Display, CPU and 3G modem). –Just by turning on Wi-Fi, standby time of the smart phone can be reduced from 350 hour to 320 hour. So, reducing the energy consumption of scanning is valuable work.

7. doc.: IEEE 802.11-12/0830r0 Submission July 2012 Yongho Seok, LG ElectronicsSlide 7 NDP Probing Procedure –STA transmit NDP Probe Request frame. SIG field may contain Access Network Option, Partial SSID. SIG field may contain Probe Response/Short Beacon Indication as the response frame of NDP Probe Request frame. –AP responses Probe Response/Short Beacon frame after back-off. Probe Response/Short Beacon frame is broadcasted. Proposed NDP Probing Procedure

8. doc.: IEEE 802.11-12/0830r0 Submission July 2012 Yongho Seok, LG ElectronicsSlide 8 Proposed NDP Probing Procedure NDP Probing Procedure –PHY-CCA.indication (busy) primitive has not been detected before the ProbeTimer reaches MinChannelTime, then set NAV to 0 and scan the next channel. [IEEE 802.11-2012] –After receiving Short Beacon/Probe Response frame, STA may transmit Probe Request frame/Association Request frame or listen to full Beacon frame for obtaining the more information.

9. doc.: IEEE 802.11-12/0830r0 Submission July 2012 Yongho Seok, LG ElectronicsSlide 9 Performance Evaluation Case 1 : Any BSS is not operating CWminMinChannelTime (TU) Energy Consumption (Current Probing) Energy Consumption (NDP Probing Option1) Gain 81= 24.18 mWxSec= 13.78 mWxSec43% 322= 30.68 mWxSec= 20.28 mWxSec34%

10. doc.: IEEE 802.11-12/0830r0 Submission July 2012 Yongho Seok, LG ElectronicsSlide 10 Performance Evaluation Case 2 : At least one BSS is operating on some 1MHz channel

11. doc.: IEEE 802.11-12/0830r0 Submission July 2012 Yongho Seok, LG ElectronicsSlide 11 Performance Evaluation Case 2 : At least one BSS is operating on some 1MHz channel –X-axis is the number of the busy channel s where at least one BSS is operating –Y-axis is the total energy consumption (mWxSec) –Left figure assume that one busy channel has only one BSS STA receives only one Probe Response frame after transmitting Probe Request frame Number of busy channels Gain mWxSec

12. doc.: IEEE 802.11-12/0830r0 Submission July 2012 Yongho Seok, LG ElectronicsSlide 12 Conclusion The energy consumption during the scanning is significantly high. –Especially, when the AP is not existing, the unnecessary scan is a problem. To solve this problem, we proposed NDP Probing Procedure. In the proposed NDP Probing Procedure, STA transmits NDP Probe Request frame and receives a Probe Response/Short Beacon frame. –The contents of SIG field is TBD.

13. doc.: IEEE 802.11-12/0830r0 Submission July 2012 Yongho Seok, LG ElectronicsSlide 13 Straw Poll 1 Do you support to define a NDP Probe Request frame with the following format? STFLTF1SIG