IEEE 802.16 MAC and PHY Specifications for Broadband WMAN 國立中興大學資工系 曾學文 Tel : (04)22840497 ext. 908 E-mail: [email protected] NCHU CSE WMAN - 1 Resources Part Source : Roger B. Marks, National Institute of Standards and Technology Boulder, Colorado, USA Chair, IEEE 802.16 Working Group http://WirelessMAN.org http://www.intel.com/idf NCHU CSE WMAN - 2 Broadband Access to Buildings • Wireless Metro Ethernet – 802.11 Wireless Ethernet • First/Last mile access – Fast local connection to network » 30%-40% Radio/TV pervasion » 5% internet access – Target Applications (similar as DSL and CableModem) » Data » Voice / Audio » Video distribution » Real-time videoconferencing • High-capacity cable/fiber to every user is expensive – Network operators demand it – Business and residential customers demand it NCHU CSE WMAN - 3 Comparisons of Wireless Standards Bandwidth Assumptions Bandwidth (MHz) 2G/2.5G 1.25 802.20 1xEV-DO, 1xEVDV, 1.25 802.20 Mobile HSDPA 5 (Vehicular) 802.16 <= 20 802.16e Bluetooth 79 x 1 MHz WWAN UWB > 100 2G/2.5G (IMT-2000) Pedestrian ® Cellularcdma2000 1xEV-DO, 802.16a (Nomadic) cdma2000® 1xEV-DV (WiMAX) Mobility WCDMA HSDPA 802.11 (WLAN) Fixed 802.15.1 802.15.3a (Stationary) (Bluetooth) (UWB) 0.1 1.0 3.1 10 100 Peak Data Rate per User (Mbits/second) Commercial Proposed Source: International Telecommunications Union and WiMAX Forum NCHU CSE WMAN - 4 Current Status • More Than 350 Operator Trials and Deployments in 65+ countries! • List of operators – http://en.wikipedia.org/wiki/List_of_Deployed_WiMAX_networks Source: Intel, the WiMAX Forum NCHU CSE WMAN - 5 4G (beyond 3G) / IMT Advanced • 4G, a term used to describe the next complete evolution in wireless communications, – is being developed to accommodate the quality of service (QoS) and rate requirements set by forthcoming applications for "anytime-anywhere". • The 4G working group has defined the following as objectives of the 4G wireless communication standard: – A nominal data rate of 100 Mbit/s while the client physically moves at high speeds relative to the station, and 1 Gbit/s while client and station are in relatively fixed positions – Smooth handoff across heterogeneous networks – Seamless connectivity and global roaming across multiple networks – High quality of service for next generation multimedia support (real time audio, high speed data, HDTV video content, mobile TV, etc) – An all IP, packet switched network. NCHU CSE WMAN - 6 Wireless Broadband Evolution to 4G NCHU CSE WMAN - 7 Pre-4G Downlink Uplink Standard Family Radio Tech Notes (Mbps) (Mbps) WiBro WiBro OFDMA 50 50 Mobile range (900 m) Quoted speeds only achievable at very 802.16e WiMAX MIMO-SOFDMA 70 70 short ranges, more practically 10 Mbit/s at 10 km. HIPERMAN HIPERMAN OFDM 56.9 56.9 5.3 1.8 Mobile range 18miles (30km) Flash-OFDM Flash-OFDM Flash-OFDM 10.6 3.6 extended range 34 miles (55km); 15.9 5.4 mobility up to 200mph (350km/h) HC- iBurst iBurst 802.20 64 64 3–12 km SDMA/TDD/MIMO UMTS HSDPA widely deployed. Typical CDMA/FDD 0.384 0.384 W-CDMA UMTS/3GSM downlink rates today 1–2 Mbit/s, ~200 14.4 5.76 HSDPA+HSUPA kbit/s uplink; HSPA+ downlink up to Source: Wikipedia NCHU CSE WMAN - 8 HSPA (High speed packet access) • HSPA+ boosts peak data rates to 42 Mbps on the downlink and 22 Mbps on the uplink – Use MIMO and higher order modulation • HSDPA (D = downlink) – 14.4 Mbps in downlink – 174 commercial networks in 76 countries – Can be achieved by software upgrade of existing 3G networks • HSUPA (U = uplink) – 5.76 Mbps in uplink NCHU CSE WMAN - 9 LTE (Long term evolution) • Third Generation Partnership Project (3GPP) Release 8 Standards in progress (expected 2009) – a project within the 3GPP to improve the UMTS mobile phone standard • Air interface is a completely new systems – based on OFDMA in the downlink and Single- carrier-FDMA (SC-FDMA has low PAPR) in the uplink that efficiently supports multi-antenna techologies (MIMO). NCHU CSE WMAN - 10 Wireless Metropolitan Area Network Relay NCHU CSE WMAN - 11 Application NCHU CSE WMAN - 12 Fixed WMAN + Mobile WMAN Source : WiMAX Forum NCHU CSE WMAN - 13 WiMAX + Wi-Fi for Mobile Internet WiMAX Outdoors Rural Tower Hot Spot Work Auto WiMAX Tower Travel Home WiMAX WiFi • Wi-Fi -> best solution for local area connectivity – With up to 450 Mbps throughput, MIMO-enabled 802.11n enables new local area applications – Wi-Fi hotspots easy to find in most places • Mobile WiMAX -> metropolitan-wide broadband coverage – Offers service providers 3x the latest HSPA (3G) capacity today – Potential to scale to over 20x the capacity of today’s HSPA via more antennas over time NCHU CSE WMAN - 14 Network Usage Model Source : WiMAX Forum NCHU CSE WMAN - 15 Features (1/2) • Broad bandwidth – Up to 134.4 Mbit/s in 28 MHz channel (in 2-66 GHz) » 32Mb/s - 134.4Mb/s (>=20MHz per channel) » 1.25/2.5/5/10/14/20/25/28MHz per channel (3.5MHz/7MHz) • Supports multiple services simultaneously with full QoS – Efficiently transport IPv4, IPv6, ATM, Ethernet, etc. – Wireless transportation system. • Bandwidth on demand (frame by frame) – Similar to HIPERLAN Type II (frame-based protocol) and DOCSIS – Centralized control • MAC designed for efficient used of spectrum • Comprehensive, modern, and extensible security ()tensions to mobility are coming next. NCHU CSE WMAN - 16 Features (2/2) • Supports multiple frequency allocations from 2-66 GHz in 802.16 (10-66GHz) , 802.16a (2-11GHz) and 802.16e (<6GHz) and 700MHz – Single carrier (SC) for line-of-sight situations – OFDM and OFDMA (MC) for non-line-of-sight situations » OFDM : orthogonal frequency division multiplexing » OFDMA : orthogonal frequency division multiple access • OFDMA = 1.25 MHz, 2.5, 5, 10, 14 and 20 MHz channels • Access schemes: – TDD (time division duplex) and FDD (frequency division duplex) • Link adaptation: Adaptive modulation and coding • Point-to-multipoint (star) topology and mesh network extension • Support for adaptive antennas and space-time coding (in 802.16a) • Extensions to mobility. (IEEE 802.16e started from Jan. 2003 and declared in 2005) NCHU CSE WMAN - 17 TDMA/OFDM/OFDMA NCHU CSE WMAN - 18 Point-to-Multipoint configuration • Two components – Subscriber Stations (SSs) » SS typically serves a building (business or residence) – Base Station (BS) » connected to public networks » BS serves Subscriber Stations » provide SS with first-mile(or last mile) access to public networks • Compared to a Wireless LAN – Multimedia QoS – Not only contention-based – Connection-oriented – Many more users – Much higher data rates – Much longer distances NCHU CSE WMAN - 19 Mesh Topology (defined in 802.16a) • Dynamic topology – Self-organizing network – More complicated NCHU CSE WMAN - 20 Relay Topology (defined in 802.16j) Mobile Multihop Relay NCHU CSE WMAN - 21 Relay Topology (defined in 802.16j) NCHU CSE WMAN - 22 Adaptive modulation and coding Full featured Standard Source : WiMAX Forum NCHU CSE WMAN - 23 WiMAX Forum • WiMAX (Worldwide Interoperability for Microwave Access) – Like WECA in IEEE 802.11 WLAN • Mission: – To promote deployment of BWA by using a global standard and certifying interoperability of products and technologies. • Principles: – Support IEEE 802.16x – 2-66 GHz (16a : 2-11GHz, 16 : 10-66GHz and 16e <6GHz) – Propose access profiles for the IEEE 802.16 standard – Guarantee known interoperability level – Open for everyone to participate • Developing & submitting baseline test specs NCHU CSE WMAN - 24 WiMAX Evolution 802.16j relay Source : Siemens, 2004 NCHU CSE WMAN - 25 IEEE 802.16 vs. ETSI • Frequent communications between 802.16 WG and ETSI (European Telecom Standards Institute) • ETSI HIPERACCESS – Above 11 GHz (outdoor , 11- 40GHz, 5Km, 25Mb/s) – ETSI began first, but IEEE finished first – 802.16 has encouraged harmonization • ETSI HIPERMAN – Below 11 GHz (outdoor) – IEEE began first HIPERMAN – Healthy cooperation – Harmonized with 802.16a OFDM • ETSI HIPERLAN • ETSI HIPERLINK –5GHz –17GHz (150m, point- (indoor/outdoor) 2-point) –6-54Mb/s –155Mb/s (OC3) –Irrelative with 802.16 –Irrelative with 802.16 NCHU CSE WMAN - 26 802.16 Standard History NCHU CSE WMAN - 28 IEEE 802.16 Standard and amendments • Fixed Broadband Wireless Access (FBWA) Systems • Air Interface (MAC and PHY) – Band 10-66GHz (ranges 1/2/3 : 10-23.5GHz/23.5-43.5GHz/43.5-66GHz) 25/28MHz per channel – line-of-sight (LOS) requirement – One PHY » WirelessMAN-SC (Single Sarrier) – Point-to-Multipoint Topology (Star) – TDD/FDD option with burst profile (depending on SNR) – Completed in October 2001 – Published in April 2002 • Follow up interoperability projects – 802.16c (Profiles): published in Jan 2003 – 802.16.1 (PICS) » PICS : Protocol Implementation Conformance Statement – 802.16.2 (“10-66GHz Coexistence of FBWA Systems”) » Focus on 23.5 to 43.5 GHz (local multipoint distribution service (LMDS), millimeter wave, etc.,) NCHU CSE WMAN - 30 IEEE 802.16a Standard • “Medium Access Control Modifications and Additional Physical Layer Specifications for 2–11 GHz” – Band 2-11GHz – Non-line-of-sight (NLOS) requirement and Multi-path issue – Near-LOS – License-exempt band 5-6 GHz (802.11a and HIPERLAN II) – Three PHYs » WirelessMAN-SC2 (single carrier) » WirelessMAN-OFDM (multiple carriers with 256-point transform) • is mandatory for license exempt bands » WirelessMAN-OFDMA (multiple carriers with 2048-point transform) • Multiple access is provided by addressing a subset of the multiple carriers to individual receivers • Scalable : 128, 512, 1024 and 2048 – Advanced Antenna Systems (AAS) (optional) – Add mesh network topology (MAC) – provide automatic repeat request (ARQ) – retransmission (MAC) – Completed in November 2002 and Approved April 2003 NCHU CSE WMAN - 31 IEEE 802.16a Standard • license-exempt bands below 11 GHz – The PHY and MAC introduce mechanisms such as dynamic frequency selection (DFS) to detect and avoid interference. NCHU CSE WMAN - 32 IEEE 802.16-2004 Standard • IEEE Std 802.16™-2004 – “Air Interface for Fixed Broadband Wireless Access Systems” - IEEE 802.16d – Approved 24 June 2004 – This standard revises and consolidates IEEE Std 802.16- 2001, IEEE Std 802.16a™-2003, and IEEE Std 802.16c™- 2002.