IEEE 802.16 and Beyond Wired to the MAX Sheraton Taipei Hotel 28-30 Sept. 2005 Ken Stanwood CEO, Vice-chair of IEEE 802.16 1
About the Speaker Ken Stanwood CEO of Vice-chair of IEEE 802.16 Co-founder of WiMAX Previous WiMAX board member 9 BWA patents and 15 applications 2
Some Terminology AP Access Point BS Base Station BWA Broadband Wireless Access DFS Dynamic Frequency Selection FEC Forward Error Correction LOS Line of Sight MIMO Multiple Input Multiple Output NLOS Non-Line of Sight OFDM Orthogonal Frequency Division Multiplexing OFDMA Orthogonal Frequency Division Multiple Access QAM Quadrature Amplitude Modulation QoS Quality of Service SoC System on a Chip SS Subscriber Station 3
Outline Introduction to 802.16 History and Purpose of WiMAX 802.16 Applications Technical Description Relationship to Other Standards Future 4
The Problem to Solve Last Mile Extension of Fiber and Cable Users want access to networks Network operators want access to customers Backhoes do not follow Moore s Law Fast local connection to network Multimedia Distribution Data Data with QoS (Gaming, etc.) Voice Video distribution Real-time videoconferencing 5
Challenges 802.16 Needed to Address Differentiated services Data Voice Video distribution Real-time videoconferencing Tough RF environments Mobility NLOS Walls Fading 6
Why not Wi-Fi or Wireless DOCSIS? Wi-Fi Designed as wireless replacement for Ethernet Less efficient use of spectrum Added priority, but not QoS CSCA great for LAN, but not multimedia Security has been improved 802.11n adding bandwidth, but not deterministic QoS Significant packet overhead DOCSIS QoS very similar Request/Grant scheme less efficient in bandwidth and delay Significant packet overhead 802.16 basic security taken from DOCSIS 802.16 message extensibility taken from DOCSIS Doesn t handle PHY changes 7
Properties of IEEE Standard 802.16 Broad bandwidth Up to 96 Mbps (>70 Mbps throughput) in 20 MHz channel (in WirelessMAN TM -OFDM air interface) Supports multiple services simultaneously with full QoS Efficiently transport IPv4, IPv6, ATM, Ethernet, etc. Bandwidth on demand (frame by frame) MAC designed for efficient use of spectrum Comprehensive, modern, and extensible security Supports frequency allocations from <1 to 66 GHz ODFM and OFDMA for non-line-of-sight applications 8
Properties of IEEE Standard 802.16 TDD and FDD Link adaptation: Adaptive modulation and coding Subscriber by subscriber, burst by burst, uplink and downlink Point-to-multipoint topology, with mesh extensions Centralized scheduling allows efficient use of available bandwidth Support for adaptive antennas and space-time coding Beamforming and MIMO Power control allows coverage from feet to miles Extensions for mobility are coming next. 9
Battery Life Power Control Subchannelization SS power amplifier Saves cost too! Beamforming Reduction in SS transmit power Sleep mode 10
Coexistence with 802.11 Compatible frequency plan Two 10 MHz (or one 20 MHz) wide channels occupy the 20 MHz of spectrum used by an 802.11 channel DFS Detect other users and select different channel Beamforming Minimize interference 11
Status of IEEE 802.16 Standards Semiconductor manufacturer s view Coming to closure slowly Mobility is bigger yet BS-BS interoperability and communication MIBs, Network, and Element management Billing, SLAs, and Authentication New features always on horizon Repeaters/Mesh 12
IEEE 802.16 Project 802.16c (2002-2004) 802.16 Amendment WiMAX System Profiles 10-66 GHz 802.16 (Dec 2001) 802.16a (Jan 2003) 802.16-2004 (Sept 2004) Original fixed wireless broadband air Interface for 10 66 GHz Line-of-sight only, Point-to-Multi-Point applications Extension (amendment) for 2-11 GHz Targeted for non line of sight, Point-to- Multi-Point applications like last mile broadband access Formerly 802.16REVd (802.16d) Consolidate 802.16, 802.16a & 802.16c and add System Profiles & Errata for 2-11 GHz in support of 802.16e requirements Prep for Mobility 13
IEEE 802.16 Project (cont d) 802.16 cor (11/2005 exp.) 802.16 Corrigendum Errata only 802.16e (11/2005 exp.) 802.16f (3/2006 exp.) Amendment for Mobile wireless broadband up to vehicular speeds in licensed bands <6 GHz Enables roaming for portable clients (laptops) within & between service areas Standardized MIBs for Fixed BWA 802.16g (1/2007 exp.) Management Plane Procedures and Services for Fixed and Mobile BWA 14
IEEE 802.16 Leadership Chair: Roger Marks Vice Chair: Ken Stanwood Secretary: Dean Chang Corrigendum Task Group Chair: Jon labs TGe Mobility Chair: Brian Kiernan TGf and TGg (MIBs and Management Plane) Chair: Phil Barber 15
Getting Involved Participation is on an individual basis Earn vote based on attendance Can earn vote based on contribution Always looking for people to help Editors Task group officers IEEE 802 Plenary meetings every March, July, and November 802.16 interim meetings every January, May, and September 16
Contributing Depends upon the status of a task group Proposals for study groups and new task groups Contribution of initial material Letter ballots Comments and comment resolution Sponsor ballots Comments and comment resolution 17
Outline Introduction to 802.16 History and Purpose of WiMAX 802.16 Applications Technical Description Relationship to Other Standards Future 18
WiMAX History First meeting April 2001 in Antibe, France Founding companies: Ensemble Nokia Harris CrossSpan Initially concentrated on 10-66 GHz Huge expansion started in Jan 2003 Intel PR engine 19
WiMAX Purpose To promote a common broadband wireless standard To develop reduced scope profiles to ease development To fill the gaps in the IEEE process relative to the ETSI process To create a broadband wireless access conformance and interoperability certification process To act as a certification body 20
Filling the Gaps - System Profiles Allow scope reduction while maintaining interoperability Targeted towards common market opportunities The most common system implementations 21
Filling the Gaps Test Specifications ETSI-style ISO/IEC 9646 compliant test specifications PICS proforma Test Suite Structure and Test Purposes (TSS&TP) Radio Conformance Test (RCT) Specification Abstract Test Suite (ATS) 22
Conformance is not Interoperability Conformance tested in independent test lab Interoperability tested via PlugFests Certification = Verified Conformance + Interoperability 23
WiMAX Certification Certifies Interoperability of equipment to other vendor s BS/SS Conformance to WiMAX defined PICS, TSS&TP based on IEEE 802.16 and ETSI HiperMAN standards IEEE 802.16 Standard ETSI HiperMAN Standard WiMAX PICS Protocol Implementation Conformance Statement WiMAX TSS&TP Test Suites Structure & Test Purposes 24
Outline Introduction to 802.16 History and Purpose of WiMAX 802.16 Applications Technical Description Relationship to Other Standards Future 25
Applications of IEEE 802.16 Fixed BWA 3G/4G Backhaul Metro Ethernet Wireless first-mile solutions Mobile BWA Mobile handheld / handsets Laptops/PDAs Government/Homeland Security First responders network Municipalities In-home Multimedia Distribution N x HDTV, VoIP, data, gaming Access points, cordless phones, adapters, appliance integration (built-ins) 26
Market Segments for Wireless Access 1 Gbps 150 Mbps FSO 50 Mbps PtP Data Rate 20 Mbps 10 Mbps 2 Mbps Point-to to-multipoint PmP 10-40GHz <11 GHz Fiber 500 kbps 56 kbps xdsl, Cable Residential SOHO Small Business Medium Business Mobile Backhaul Addressable Markets Multi- Tenant Residential Large Business 27
802.16 BWA in Metro Ethernet Ethernet UNI EVC 1 Optical Metro Ethernet CE 802.16 SS EVC 2 CE Ethernet UNI 802.16 SS EVC 3 802.16 Base Station Ethernet Backhaul 28
Wireless Tower and Hot Spot Backhaul Highly Scalable Highly reliable Copper T1 s are the biggest reliability issue in the network today Simple & quick Provisioning Low cost nxt1 capability TNC PMP Range PtP Range 29
Selecting an IEEE 802.16 PHY WirelessMAN-SC Targeting market above 11 GHz LOS WirelessMAN-SCa Targeting market below 11 GHz Very little industry support Mostly LOS WirelessMAN-OFDM Targeting Market below 6 GHz NLOS and Near LOS operation Current choice for fixed systems WirelessMAN-OFDMA (scalable) Targeting Market below 6 GHz NLOS and Near LOS operation Current choice for mobile systems 30
Outline Introduction to 802.16 History and Purpose of WiMAX 802.16 Applications Technical Description Relationship to Other Standards Future 31
Reference Model 32
3 rd Gen. Technology in 802.16 QPSK Q16 Q64 distance Adaptive Modulation & FEC variable modulation & coding maximizes both air-link capacity and coverage time frequency Adaptive TDMA True bandwidth on demand and variable packet sizes provide differentiated, bursty services to multiple users Adaptive TDD variable asymmetry in a single broadband channel best matches bandwidth to demand 33
Adaptive Burst Profiles Burst profile Modulation and FEC Dynamically assigned according to link conditions Burst by burst, per subscriber station Trade-off capacity vs. robustness in real time Roughly doubled capacity for the same cell area Burst profile for downlink broadcast channel is wellknown and robust Other burst profiles can be configured on the fly SS capabilities recognized at registration 34
Coverage/Capacity Advantage of Adaptive PHY 2-3km* 2-3km* QAM-64 100% of Channel Capacity 99.95%* ~ 364 days 19.5 hrs/yr QPSK QAM-16 QAM-16 QAM-64 QAM-64 85% of Channel Capacity 99.993% ~ 4 hrs/yr QPSK QAM-16 QAM-64 70% Channel Capacity 99.999%, ~ 20 min/yr Burst profile changes dynamically to match propagation path conditions 35
Dedicated, Fixed Symmetry with FDD 36
Spectral Efficiency with Adaptive TDD 37
802.16 Supports MIMO MIMO uses multiple antenna and RF architectures. This can be used to provide an increase in system gain or capacity or a combination of both System gain improvements (link budget gains) are seen when using Alamouti STC spatial diversity System capacity improvements are seen when using spatial multiplexing In 802.16 both are supported by the use of MIMO options. 38
802.16 Supports Beamforming (AAS) High system gain for maximum coverage and availability Use for extended range or increased capacity Penetrate walls Null interferers Reduction in overall levels of interference SS can be omni-directional Modified frame structure for network entry in 802.16 Technology well suited to a macro cellular propagation environment The physical layer of 802.16 supports mechanisms for mesh realization using MIMO and AAS 39
Coverage of Downtown L.A. PMP >6km >10km PtP Sufficient range to cover entire downtown area 40
802.16 MAC: Highlights Point-to-Multipoint Connection-oriented Supports difficult user environments High bandwidth, hundreds of users per channel Continuous and burst traffic Very efficient use of spectrum Protocol-Independent core (ATM, IP, Ethernet, ) Balances between stability of contentionless and efficiency of contention-based operation Flexible QoS offerings CBR, rt-vbr, extended rt-vbr, nrt-vbr, BE, with granularity within classes Supports multiple 802.16 PHYs 41
IEEE 802.16 MAC Three Sublayers Service Specific Convergence Sublayer (CS) Mapping upper-layer data into MAC SDUs upper-layer data traffic classifications Payload header suppression (PHS) -- Optional MAC Common Part Sublayer (MAC CPS) System access control MAC PDU encoding and decoding Bandwidth management QoS provision Privacy Sublayer Secures over-the-air transmissions Protects from theft of service 42
ATM Convergence Sublayer Full QoS support Support for end-to-end signaling of dynamically created connections SVCs & soft PVCs Support for VP (Virtual Path) and VC (Virtual Channel) switched connections ATM header suppression 43
Packet Convergence Sublayer Support for Ethernet, VLAN, IPv4 and IPv6 based services Full QoS support Payload header suppression 44
Some MAC Considerations Address the Wireless environment Different transport protocols ATM, IP Broadband services Very high bit rates, downlink and uplink Different QoS requirements Likelihood of Terminal being shared Combined with previous issue may heavily load Base Station Network Access Security 45
802.16 QoS Building Blocks Four classes of service Constant rate Real-time variable rate Non real-time variable rate Best effort Extended real-time variable rate (hybrid of constant rate and rt variable rate) QoS and Traffic Parameters Maximum bit rates Guaranteed bit rates Priority Delay Jitter 46
802.16 QoS Building Blocks Clock regeneration Regeneration of multiple network clocks Centralized scheduling to maximize throughput Still subject to implementation quality Fairness algorithms Call admission control Request/grant 47
Centralized Scheduling with Just a Touch of Chaos Self-correcting protocol No acknowledgements Discrepancies BS did not hear request SS did not hear grant Bandwidth stealing Packing and fragmentation overhead Insufficient bandwidth Tools Incremental and Aggregate BW requests Zero-length bandwidth requests 48
Centralized Scheduling with Just a Touch of Chaos Request by connection Necessary for fairness/qos calculations Grant by terminal Efficiency Flexibility Request/Grant Strategies Unsolicited grants Polling unicast, multicast, broadcast Piggybacking Bandwidth stealing 49
MAC PDU Transmission MAC Message SDU 1 SDU 2 Fragmentation Packing MAC PDUs PDU 1 PDU 2 PDU 3 PDU 4 PDU 5 Concatenation Burst P FEC 1 FEC 2 FEC 3 Shortening MAC PDUs P Preamble FEC block 50
Multiple Access and Duplexing On DL, SS addressed in TDM stream On UL, SS allotted a variable length TDMA slot Time-Division Duplex (TDD) DL & UL time-share the same RF channel Dynamic asymmetry SS does not transmit/receive simultaneously (low cost) Frequency-Division Duplex (FDD) Downlink & Uplink on separate RF channels Static asymmetry Half-duplex SSs supported SS does not transmit/receive simultaneously (low cost) 51
802.16e Frame-Based Transmission Frame duration is specified by frame duration code in DL-MAP, broadcast at beginning of every MAC frame Possible frame durations vary by PHY choice BS TDD turn-around time: TTG: Transmit/receive Transition Gap RTG: Receive/transmit Transition Gap Specified in DCD message SS/MS TDD/H-FDD turn-around time: SSTTG: SS TTG SSRTG: SS RTG Specified in SBC-xxx messages 52
Downlink Subframe TDMA portion: transmits data to some half-duplex SSs (the ones scheduled to transmit earlier in the frame than they receive) Need preamble to re-sync (carrier phase) 53
Typical Uplink Subframe 54
Burst Structure Concatenation Combining 2 or more MAC PDUs into one PHY burst Packing Combining 2 or more MAC SDUs (or fragments) into on MAC PDU Fragmentation Payload header suppression (PHS) 55
Security and Encryption Provide extensible privacy, theft of service protection Authentication Based on RSA public key and X.509 certificate Authenticate terminals Authenticate connection establishment Encryption 56-bit DES CBC or 128 bit AES Protocol is modification of BPI+ (from DOCSIS) 802.16e is extending to equivalent of 802.1x 56
Overview of 802.16 PHYs SC SCa OFDM OFDMA Spectrum 10 66GHz below 11 GHz below 11 GHz below 11 GHz Channel condition LOS only LOS only Designed for NLOS Designed for NLOS Cell Raius 2 to 5 Km 5 to 12 Km 5 to 12 Km 5 to 12 Km Channel Bandwidth Duplexing Mode Modulation 20, 25, & 28 MHz 1.25 to 20 MHZ (flexible) 1.25 to 20 MHZ (flexible) 1.25 to 20 MHZ (flexible) TDD/FDD TDD/FDD TDD/FDD TDD/FDD Single carrier: QPSK, 16QAM, 64QAM Raw Bit Rate 32 to 134.4 Mbps Single carrier: QPSK, 16QAM, 64QAM, 256QAM OFDM (256 FFT): BPSK, QPSK, 16QAM, 64QAM OFDM (128, 512, 1K, & 2k FFT): BPSK, QPSK, 16QAM, 64QAM 1 to 75 Mbps 1 to 75 Mbps 1 to 75 Mbps 57
Physical Layer Tools Subscriber level adaptive physical layer Subchannelization OFDM/OFDMA for mobility Beamforming MIMO Space-Time Coding (STC) Dynamic Frequency Selection - DFS 58
802.16 SC PHY Specifics 59
802.16 SC PHY Specifics Modulation choices: QPSK 16QAM 64QAM FEC Reed Solomon For robust communications the RS code is concatenated with a BCC Turbo Codes (TPC) are optional Frame length is either 0.5, 1 or 2 ms As baud rate increases smaller frames are used 60
SC PHY: Baud Rates & Channel Size Flexible plan - equipment manufactures choose according to spectrum requirements 10 to 32 MBaud Recommended baud rates in the standard are suitable for worldwide deployments 28 MHz (22.4 MBaud) 25 MHz (20 Mbaud) Frame length is tied to the baud rate 61
802.16 OFDM PHY Specifics 62
802.16 OFDM PHY Overview below GHz 256-point FFT 192 data carriers + 8 pilot carriers = 200 active carriers Concatenated coding for forward error correction (FEC) Optional Turbo Coding BPSK, QPSK, 16-QAM, 64-QAM (optional) with various coding rates subchannelization optional 63
OFDM Symbol Time Domain Frequency Domain 64
IEEE 802.16 MAC OFDM PHY TDD Frame Structure Time Frame n-1 Frame n Frame n+1 Adaptive DL Subframe UL subframe pre. FCH DL burst 1 DL TDM DL burst 2... DL burst n pre. UL burst 1 UL TDMA... pre. UL burst m DL MAP UL MAP DCD opt. UCD opt. Broadcast Conrol msgs 65
IEEE 802.16a MAC OFDM PHY FDD Frame Structure Time Frame n-1 Frame n Frame n+1 DL Subframe DL TDM DL TDMA pre. FCH DL burst 1 DL burst 2... DL burst k pre. DL burst k+1... pre. DL burst n Broadcast Control Msgs DL MAP UL MAP DCD opt. UCD opt. UL subframe UL MAP for next MAC frame UL bursts pre. UL burst 1 UL TDMA... pre. UL burst m 66
OFDM PHY: Raw Bit Rate (Mbps) Modulation / Code Rate QPSK 3/4 16 QAM 1/2 16 QAM 3/4 64 QAM 2/3 64 QAM 3/4 1.75MHz 2.18 2.91 4.36 5.94 6.55 3.5MHz 4.37 5.82 8.73 11.88 13.09 7.0 MHz 8.73 11.64 17.45 23.75 26.18 10.0MHz 12.47 16.63 24.94 33.25 37.40 20.0MHz 24.94 33.25 49.87 66.49 74.81 67
802.16 OFDMA PHY Specifics 68
Below 6 GHz 802.16 OFDMA PHY Overview 128, 512, 1024, or 2048-point FFT Concatenated coding for forward error correction Optional Turbo Coding Scrambler is used to randomize the data QPSK, 16-QAM, 64-QAM (optional) with various coding rates subchannelization mandatory 69
Some OFDMA Basic Terms Subchannel A subset of active subcarriers Permutation the way how subcarriers form subchannels, e.g., adjacent or distributed, ect. Permutation Zone A number of contiguous OFDMA symbols, in the UL or DL, that use the same permutation formula. Segment A set of subchannels that are used for deploying a single instance of the MAC. 70
OFDMA Frame Structure 71
802.16e OFDMA Frame With Multiple Permutation Zones 72
OFDMA: Multiple Different Permutations PUSC Partial Usage of SubChannels: not all the subchannels are allocated to the transmitter; Divide the subcarriers into clusters with zero carriers allocated, and then allocate pilots and data carriers in each cluster. Optional PUSC Additional optional symbol structure for PUSC UL only FUSC Full Usage of SubChannels: all subchannels are allocated to the transmitter; Allocate pilots with zero subcarriers, then allocate data subcarriers. DL only Optional FUSC Additional optional symbol structure for FUSU DL only. AMC Advanced Modulation/Coding (bad name!) Adjacent subcarrier permutation TUSC1 Tile Usage of SubChannels 1 DL only AAS zone only TUSC2 Tile Usage of SubChannels 2 DL only AAS Zone only 73
OFDMA Allocation Terms slot Minimum allocation unit; The definition of a slot varies with: UL / DL Permutations Data Region A two-dimensional allocation of a group of contiguous subchannels, in a group of contiguous OFDMA symbols. 74
OFDMA Allocation Unit --- Slot Definitions Permutations DL Slot definition UL Slot definition PUSC Optional UL PUSC FUSC Optional DL FUSC AMC DL TUSC1 DL TUSC2 One subchannel by Two OFDMA symbols n/a One subchannel by One OFDMA symbols One subchannel by One OFDMA symbols One subchannel by One OFDMA symbols One subchannel by Three OFDMA symbols One subchannel by Three OFDMA symbols One subchannel by Three OFDMA symbols One subchannel by Three OFDMA symbols n/a n/a One subchannel by One OFDMA symbols n/a n/a 75
76 OFDMA DL Allocation and Data Mapping Optional FUSC FUSC (DL_PermBase 0) FUSC (DL_PermBase Z) PUSC (DL_PermBase Y) PUSC (DL_PermBase 0, containing FCH and DL-MAP) Preamble preamble 0 1 2.. L -1 Subchannel Index
OFDMA UL Burst Allocation and Data Mapping PUSC UL slot = 1 subchannel * 3 symbols PUSC Zone UL Subframe Optional PUSC zone OFDMA data Symbol index text AMC zone 0 1 2 3 4 5 6 7.. m Slot 0 Slot 1 Slot 2 Slot 3 Slot 4 UL Burst #1 UL Burst #2 UL Burst #3 UL Burst #5 UL Burst #4 Slot k Slot k+1 Burst allocated by UIUC=12 Slot k+2 Slot k+3 Slot k+4 Two types of UL allocation: Block allocation (two dimensional: subchannel by symbol) UIUC=0, 12, 0r 13 Specified by Symbol offset Subchannel offset Number of symbols Number of subchannels Slot allocation (linear: duration in slots) UIUC = 1 to 10 Specified by number of slots Allocated in time-domain first manner, i.e., symbol-first, then subchannels Not more than one UL-MAP IE with UICU=1 to 10 for a SS Data mapping in an UL allocation frequency-domain first, then time-domain, i.e., subchannel-first, then symbols. Skip the allocations made by IEs with block allocations. Not more than one UL burst with burst profile UIUC= 1 to 10 for each SS in an UL subframe; (this does not apply to HARQ regions). -- UL data mapping in an UL burst, frequency-domain first, then time-domain -- skip the blocks allocated by the block allocaitns UL burst allocation, time-domain first, then freqeuncydomain 77
Outline Introduction to 802.16 History and Purpose of WiMAX 802.16 Applications Technical Description Relationship to Other Standards Future 78
Creating a Standard Different strategies Try to get an existing, proprietary system standardized (IS-94, 802.20) Come with proposal to new working group for future system (802.16) Different standards body procedures IEEE 802 ETSI CEA 79
802.16 and ETSI Over 50 liaison letters between 802.16 and ETSI (European Telecom Standards Institute) ETSI HIPERMAN Below 11 GHz Healthy cooperation Harmonized with WirelessMAN TM- OFDM 80
802.16 and ITU ITU-T January 2004: 802.16 approved as draft recommendation for wireless extension of cable operator footprint. Included in-home ITU-R November 2004: Liaison statement Return statement from 802.16 Working towards ITU BWA recommendation 81
802.16 and WiBro Numerous liaison letters between 802.16 and WiBro WiBro very similar to subset of 802.16e Healthy cooperation with WirelessMAN-SCa On-going harmonization 82
IEEE 802.20, 21, and 22 802.20 Billed as broadband mobility Off to a very slow start Recent events my revitalize, but could lead to a 1 company solution 802.21 Media independent handoff between the different 802 standards 802.3, 802.15, 802.11, 802.16, etc. 802.22 Use unused but licensed TV spectrum 6 MHz channels Some interest in using 802.16 Wireless microphones are incumbent but 95% illegally used 83
Outline Introduction to 802.16 History and Purpose of WiMAX 802.16 Applications Technical Description Relationship to Other Standards Future 84
Extending 802.16 Applicability 85
Basic Premise It is desirable for the home or office to operate wirelessly The home and office require a multitude of media to coexist simultaneously without interfering with each other Certain applications cannot tolerate a degradation in service Compatibility between indoor and outdoor applications is desirable 86
What Does This Mean to the Home? Proper BWA requires a solution for high QoS multimedia in a low resource situation with a tough RF environment The home requires a solution for high QoS multimedia in a low resource situation with a tough RF environment 802.16 is designed to solve both problems 87
Guaranteed Data Access Vision - Wireless Multimedia Distribution in the home Broadband Service 802.16, Cable, DSL, IP Set Top Box WiMAX 802.16/11 AP Real-Time Video 2xHDTV 802.16 Real-Time Video 2xHDTV 802.16 Tablet PC with Camera CBR TDM Voice Real-Time Video 2xHDTV Cordless Phone Guaranteed and Best Effort Access Best Effort Access 802.16 802.16 802.16 802.16/11 802.16/11 Gaming HDTV Pocket PC 88
Extending the Triple-Play The Quadruple-Play 4 classes of service Voice Video Best Effort data Data with guaranteed QoS Priority is NOT QoS Extra bandwidth is NOT QoS 89
Always Best Connected Laptop or other device with both 802.11 and 802.16 capability 802.16e mobile data/voice device Transition outdoors-indoors Cordless phone is mobile phone 90
Complementary Capabilities IEEE 802.16/WiMAX Distribution Strict QoS Mobility IEEE 802.11/Wi-Fi Data LAN Extensive Availability IEEE 802.15.x Cable Elimination Low Power Numerous Application Specific Variants 91
Hierarchical Systems INDOOR CPE MMDS Band Non Line of Sight Point to Multi-point BACKHAUL Point to Point 802.11 & 802.16 INTERNET BACKBONE 92
Always best connected Cygnus 802.16 SS ASIC Cygnus 802.16 SS ASIC Nomadic Notebook PC Cordless Phone or Mobile Handset Cordless Phone or Mobile Handset Tuner Tuner Cygnus 802.16e SS ASIC Memory Network Processor VOIP 10/100 BaseT LAN Ports 802.11a,g AP Cygnus 802.16e AP ASIC Cygnus 802.16 SS ASIC Cygnus 802.16 BS SDR Voice Ports Notebook PC 802.16 Base Station Cygnus 802.16 SS ASIC Game console 93
Connection Management in the Home Supporting true QoS End-to-end or local? The dynamics of selforganization Service Level Agreement (SLA) vs. free or bundled Call admission control (CAC), Congestion Avoidance, reaction to changing RF and interference environment Dynamic Service Allocation (DSA) Classification Roaming Theft of service Digital Rights Management (DRM) 94
Can 802.16 Meet the Price Point? SS ASICs will follow 802.11 price curve AP/BS ASICs are coming Needed for price point Asymmetric protocol a SS is not an AP Request/grant Subchannelization Beamforming Needed for size Needed for heat dissipation 95
What Does This Mean to BWA? A true BS SoC allows traditional BWA to be driven down to <$100 per channel Decreased power and heat pico base stations powered over their Ethernet backhauls Advanced techniques such as beamforming open the door for self install reduced OpEx 96
Mesh 97
Why Mesh? Communication within a local community How often is this true? Capacity increase Obvious if local community Difficult to achieve otherwise Alternative path Modeled after the core network Cost effective range extension Reduce base station nodes while user community sparse Is the mesh a mesh or a tree? How rich is the mesh? Increased riches provides resiliency, but presents a more complex planning and management task. 98
Advantages of Mesh Adds capacity under the right circumstances Supports scalability, reduces infrastructure costs Increases range and steers around LOS blockages Resilience to unit failure with the provision of backup paths As the network grows and becomes more dense then average power reduces and probability of coverage increases Potential for very high spectral efficiencies dependent on antenna technology used 99
Challenges for Mesh Delays incurred with multiple hops and processing delay preservation of QoS Cost of network elements in the limit requirements for a combined BS/CPE solution Incremental cost of planning and management Increased cost associated with support for routing functionality and possible propriety signaling. Possible frame structure dependencies for interference avoidance in license-exempt spectrum coordinated avoidance Capacity constraints at branch/mesh extremities & necessity for high capacity at mesh ingress points Possible requirements for timing synchronization 100
Mesh Realization Broadly speaking there are two realizations for mesh: logical and physical - driven by the antenna technology employed and requisite support of network management Logical mesh Use broad beam or omni-directional antennas to form logical links to neighboring devices Links are therefore logical in the respect that the hardware configuration is unaltered for different links Link information is maintained by network management entities Physical mesh Use substantially directional antennas to create physical links Links are therefore a physical realization as the hardware configuration changes to form links to neighboring devices Steers beams either electrically or mechanically Both realizations have their own benefits and challenges 101
Logical Mesh Lower C/I and spectral efficiency High reuse factor Intra network interference needs protocol support Significant impact of external interference on large parts of the network Supporting a rich mesh can be difficult with few frequencies due to high reuse factor requirements Adding a new node adds intra mesh interference Interference impact on reuse 102
Significantly improved C/I Low frequency reuse High spectral efficiency Complications for network entry More expensive antenna systems Complex environment sensing with mechanical antennas Physical Mesh Interference impact on reuse reduced due to a smaller arc of impact Adding a new node adds intra mesh interference 103
Mesh Architectures Both logical and physical meshes share categories of repeaters that can be implemented RF repeaters: RF repeaters simply receive on one frequency and transmit on another, given sufficient spatial isolation the same frequency could be used PHY and MAC repeaters: PHY repeaters and MAC repeaters do increasingly more processing of the signal before forwarding it. They have the advantage of being able to be more intelligent about re-amplification of signals, but at the cost of delay and complexity. In the limit, a MAC level repeater becomes simply another BS or Ethernet bridge Network level repeaters: Use routing functionality to direct IP datagrams through the multi-hop system 104
Mesh in 802.16 Currently in the Standard The mesh mode in 802.16-2004 is a logical mesh. It supports interference mitigation with MAC message support for scheduling. This mesh is self organizing mesh which consumes bandwidth and compromises QoS. This is built on top of standard PMP Uses the OFDM PHY Designed primarily for cost-effective build out and range extension whilst the user community sparse. Not designed for local community communication All data goes back through an ingress/egress point Not designed for capacity increase Can provide alternative, backup paths Assumes omni-directional antennas Developed by Nokia in support of their RoofTop product line DM (Directed Mesh) is a physical mesh and is supported in SC PHY (10-66GHz) only. It is based on a configuration of PMP mode. Used with directional antennas Developed by Radiant Networks to support their MESHWORKS products Both mesh implementations are currently unsupported in the standard 105
PHY Support for Mesh in 802.16 802.16 provides: AAS (Advanced Antenna System) supporting beamforming MIMO (Multiple Input Multiple Output) supporting: Spatial diversity schemes (Space Time Coding) Spatial Multiplexing Combination of the two techniques Exploitation of diversity and advanced antenna techniques for user installability and system gain enhancements Together with interference management in license exempt bands all require careful consideration for WiMAX mesh 106
Mesh in 802.16 for Future Development New Group meeting for the first time at 802.16 interim in May 2005 Mobile Multi-hop Mesh Networking. The group s scope includes Compatibility with PMP: 802.16-2004 and 802.16e Efficient mesh/relay to MS (Mobile Station) OFDM/OFDMA PHY support Tentative schedule sees Study Group formed in Sept. 2005 and Task Group initiated in May 2006 Downlink Relay Uplink Mesh is currently a topic generating significant interest and contribution into the standard 107
Mesh System Concept 2.5GHz band Non Line of Sight Point to Multi-point >26GHz Backhaul Point to Point/Multi-point 802.16 802.11 & 802.16 802.16 INTERNET BACKBONE 108
A Mesh Example SS SS BS SS BS SS SS Mesh SS BS SS No coverage BS SS Mesh coverage BS SS SS Three BS required for full coverage Two BS required with mesh SS 109
Predictions WirelessMAN TM -OFDMA (802.16e) will be the winner Fixed systems will benefit from increased volumes Fixed systems need the option to be fixed/mobile hybrids WiBro and near-wibro will be the profiles of choice TTA in Korea is settling on 802.16e options subset that satisfy needs for mobile and fixed Don t fragment the market Need channel width and duplexing flexibility for other countries The really big market is not BWA, but in-home multimedia distribution In-home multimedia distribution Mobile applications Government/Homeland defense applications Fixed BWA Mesh attributes will play an important role in successful systems 110
Thank You Any questions? info@cygnuscom.com Address: 2075 Las Palmas Drive Carlsbad, CA 92009 www.cygnuscom.com 111