IEEE 802.11 WLAN Standardization LG전자차세대통신연구소석용호책임연구원 (yongho.seok@lge.com)
Outline Wi-Fi network: state of the art Gigabit Wi-Fi (IEEE 802.11ac/ad) Extended Wi-Fi (IEEE 802.11af/ah) Future Wi-Fi Technology and Application 1
PHY Wi-Fi network: state of the art MAC Smart Grid WNG Discussion Topics IDS CMMW Study groups 802.11ai FILS 802.11 ah 802.11af TVWS TG without Approved draft 802.11ac VHT 5GHz WG Letter Ballot Slide 2 2 802.11ad VHT 60 GHz Sponsor Ballot 802.11s Mesh 802.11u WIEN 802.11V Network Management 802.11aa Video Transport 802.11ae QoS Mgt Frames 802.11mb Revision 802.11z TDLS 802.11r Fast Roam 802.11k RRM 802.11Y Contention Based Protocol 802.11p WAVE 802.11n High Throughput (>100 Mbps) 802.11W Management Frame Security Published Amendment 802.11-2007 e QoS h DFS & TPC i Security f Inter AP j JP bands g 54 Mbps 2.4GHz 802.11-2003 b 11Mbps 2.4 GHz a 54 Mbps 5GHz 802.11 ( 99) 2.4GHz Published Standard d
MAC 802.11-1999 PHY Wi-Fi network: state of the art d Intl roaming a 54 Mbps 5GHz b 11 Mbps 2.4GHz 802.11-2003 e QoS h DFS & TPC i Security f Inter AP j JP bands g 54 Mbps 2.4GHz 802.11-2007 802.11z TDLS 802.11r Fast Roam 802.11k RRM 802.11Y Contention Based Protocol 802.11p WAVE 802.11n High Throughput (>100 Mbps) 802.11W Management Frame Security 802.11s Mesh 802.11u WIEN 802.11V Network Management 802.11-2012 802.11ai FILS 802.11ae QoS Mgt Frames 802.11aa Video Transport 802.11af TV Whitespace 802.11ac Very High Throughput 6Gbps @ 5GHz 802.11ad Very High Throughput 6Gbps @ 60GHz 802.11ah <1GHz 3
Gigabit Wi-Fi (IEEE 802.11ac) Goal A maximum multi-sta throughput of at least 1Gbps and a maximum single link throughput of at least 500Mbps Technology Comparison between 802.11a/n/ac 802.11a 802.11n 802.11ac Frequency band 5 GHz only 2.4 GHz/5 GHz 5 GHz only Channel Bandwidth 20 MHz 20 MHZ/40 MHz 20 MHz/40 MHz/ 80 MHz/160 MHz/80+80 MHz Number of Spatial Stream 1 1~4 1~8 Peak PHY Rate 54 Mbps 600 Mbps 6.9 Gbps Key Technology OFDM MIMO MU-MIMO 4
Gigabit Wi-Fi (IEEE 802.11ac) VHT SG focus: - Throughput : Maximum channel bandwidth ~ 80 MHz and Peak Data Rate at least 2 Gbps - Range: Provide better/higher data rates at longer range than what is available with TGn -Power: Power consumption for traffic upload or download should not be more than half of what it would be when using TGn power save features and at the same range Discussion on Propatation between 60GHz and 5GHz: - Pathloss - PA Power - Blockage effect - etc Split!! Conclusion: 60 GHz frequency band may not be suitable for applications that require similar range requirements and applications as 802.11a/b/g/n systems. VHTL6 IEEE802.11ac VHT60 IEEE802.11ad 5
Gigabit Wi-Fi (IEEE 802.11ac) Cloud Back Up Drive Kids Room Surveillance Video Cam Cable / DSL Modem WLAN Bridge NAS Drive IPTV Box e.g. Roku Kids Surveillance Monitor DTV1 Entertainment PC DTV2 Car Video Content Server Car Parked in Carport 6
Gigabit Wi-Fi (IEEE 802.11ac) Higher MIMO, Wider bandwidth, and Higher MCS are introduced 11n 11ac SU-MIMO Up-to 4 spatial streams. Up-to 8 spatial streams MU-MIMO Not defined. Defined in AP-to-Non_AP STA: - Max # of Nss per user in MU: 4 - Max # of MU users: 4 - Max # of Nss over all users in MU: 8 Bandwidth Maximum 40MHz Maximum 160MHz - Mandatory: 20/40/80MHz - Optional: 160MHz, 80+80MHz MCS BPSK, QPSK, 64QAM BPSK, QPSK, 64QAM, 256 QAM (optional) Max Throughput 600 Mbps 11.5 6933.3 Mbps times 7
Gigabit Wi-Fi (IEEE 802.11ad) Goal A maximum single link throughput of at least 1Gbps Technology Comparison between 802.11ac/ad 802.11ac 802.11ad Frequency band 5 GHz only 60 GHz only Channel Bandwidth 20 MHz/40 MHz/ 80 MHz/160 MHz/80+80 MHz 2.16 GHz Number of Spatial Stream 1~8 1 Peak PHY Rate 6.9 Gbps 6.7 Gbps Key Technology MU-MIMO Directional antenna 8
Gigabit Wi-Fi (IEEE 802.11ad) Rapid Upload / Download Wireless Display WLAN clip/movie ~1Gbps Range <3-8m, LOS, specific placement Latency ~ ok 1080p today (~3Gbps) Max rate + compression Range 5-10m, NLOS Latency < 15ms (gaming) Max Avail Bandwidth Efficient handling of Mixed types Range 5-10m, ~NLOS Latency < 30ms 9
Gigabit Wi-Fi (IEEE 802.11ad) Usages are peer-to-peer (ad-hoc) in nature No device is dedicated for a particular function All devices in the network perform the role of a content consumer or content creator or both Access to WLAN infrastructure may not be required in all cases In order to achieve higher throughputs directional antennas are key to any design This can be achieved through antenna arrays which helps to steer the beam in one direction or through sectorized antennas Sector sweeping Directional communication: efficient, high rate Omni communication: expensive, much lower rate or shorter range 10
Extended Wi-Fi (IEEE 802.11af) Goal Define modifications to both the 802.11 physical layers (PHY) and the 802.11 Medium Access Control Layer (MAC), to meet the legal requirements for channel access and coexistence in the TV White Space Technology Comparison between 802.11ac/af 802.11ac 802.11af Frequency band 5 GHz only TV White Space only (e.g., 54~72, 76~88, 174~216 470~698MHz) Channel Bandwidth 20 MHz/40 MHz/ 80 MHz/160 MHz/80+80 MHz 4/8/16/32 MHz (not decided yes) Number of Spatial Stream 1~8 4 (not decided yet) Peak PHY Rate 6.9 Gbps TBD Service Coverage <250m < 1Km 11
Extended Wi-Fi (IEEE 802.11af) A/V Streaming throughout entire household Cellular Traffic Offloading Key Requirements: Protection to the incumbent users, to meet legal requirements Appropriate data rates to provide good user experience with extended coverage area 12
Extended Wi-Fi (IEEE 802.11af) In November 2008, the FCC approved the use of White Spaces by unlicensed devices, which introduced up to a total of 180 MHz available for portable operation. The final rules from the FCC where announced in late 2010. Similarly Ofcom is working on developing white space rule for UK territory, and it will be finalized before the end of year 2012. Regulators around the world are interested in the use of geo-location database techniques to enable the use of White Spaces. IEEE 802.11 TGaf is currently working on the standard wireless LAN operation on White Spaces. General rule for White Space is Devices should transmit after querying a database
Extended Wi-Fi (IEEE 802.11af) White Space Map (WSM)
Extended Wi-Fi (IEEE 802.11af) Contact Verification Signal (CVS)
Extended Wi-Fi (IEEE 802.11af) The PHY for one TVWS channel (6MHz, 7MHz or 8MHz) is based on the 40MHz 128FFT VHT PHY. Support for multi-channel coexistence : The pre-vht fields shall be placed around the middle of each TVWS channel irrespective of the number and location of the channels used for transmission 16
Extended Wi-Fi (IEEE 802.11ah) Goal Defines enhancements to the IEEE 802.11 Medium Access Control (MAC) to support an Orthogonal Frequency Division Multiplexing (OFDM) Physical layer (PHY) operating in the license-exempt bands below 1 GHz, e.g., 868-868.6 MHz (Europe), 950 MHz -958 MHz (Japan), 314-316 MHz, 430-434 MHz, 470-510 MHz, and 779-787 MHz (China), 917 923.5 MHz (Korea) and 902-928 MHz (USA) Technology Comparison between 802.11af/ah Frequency band Channel Bandwidth 802.11af TV White Space only (e.g., 54~72, 76~88, 174~216 470~698MHz) 4/8/16/32 MHz (not decided yes) 802.11ah Below 1 GHz excluding the TV White Space bands (e.g., 902~928MHz) 1/2/4/8/16 MHz Number of Spatial Stream 4 (not decided yet) 4 Peak PHY Rate TBD TBD Service Coverage < 1Km < 1Km Supported maximum STAs 2,007 About 8,000 17
Extended Wi-Fi (IEEE 802.11ah) Use Cases: Smart Grid Meter to Pole Distributed Automation Device Data Collector & Control IEEE 802.11ah AP Gas Meter Water Meter Distributed Automation Device Power Meter Wide Area Neighbor Area Home Area Proposed infrastructure Wireless communication link Wired communication link 18
Extended Wi-Fi (IEEE 802.11ah) Hierarchical Structure of Traffic Indication Map Divide the total AID space into small blocks in a hierarchical manner and transmit only the blocks with non-zero values Easier to break a large TIM into small groups of STAs and easier to maintain Different classes of STAs can be easily grouped into different groups/pages (e.g. Sensor STAs in Page 1 and Offloading STAs in Page 2) Three level hierarchy: Page/Block/Sub-Block Supporting max TBD STAs (e.g. 8192) N P (e.g. 4) Pages: Page 1 Page 2 Page 3 Page 4 2048 STAs N B (e.g. 32) Blocks: Block1 Block2 Block3 Block4 Block5 Block6 Block7 Block8 Block31 Block32 64 STAs 8 Sub-blocks: 1 octet = 8 STAs 19
Extended Wi-Fi (IEEE 802.11ah) The STAs can be grouped into AID groups/pages STAs supporting different use cases can be easily grouped into different Pages Sensor stations (infrequent traffics) Page 1 Offloading stations (frequent traffics) Page 2 20
Future Wi-Fi Technology and Application Future Wi-Fi Technology Gigabit Wi-Fi Wi-Fi VHT5G : certification program of IEEE 802.11ac Wi-Fi 60G : certification program of IEEE 802.11ad Extended Wi-Fi Wi-Fi TVWS (TV Whitespace) : certification program of IEEE 802.11af Low Power Wi-Fi Wi-Fi NPS (Network Power Save) : certification program of IEEE 802.11v Wi-Fi Power Conservation Future Wi-Fi Application Wi-Fi HotSpot 2.0 : certification program of IEEE 802.11u Wi-Fi Display, Wi-Fi Serial BUS, Wi-Fi Docking, Wi-Fi NAN (Neighbor Awareness Network) 21
Conclusion 1 st Generation (1997) IEEE 802.11 (2Mbps) 2 nd Generation (1999) IEEE 802.11b (11Mbps) 3 rd Generation (2002) IEEE 802.11g/a (54Mbps) 4 th Generation (2007) IEEE 802.11n (Up to 600Mbps, Most common is 150Mbps) 5 th Generation (2012) IEEE 802.11ac (Up to 6.9Gbps, First solution is 1.3Gbps) 6 th Generation (????) IEEE 802.11af, IEEE 802.11ah : Super Wi-Fi, M2M/IoT 22
References 11-12-0182-01-0000-802-11-snapshots-march-2012 23