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Microsoft PowerPoint - WiMax-Architecture

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					                                                                           Wireless Communication Networks
                                                                           Wireless Wide                                             WWAN
                                                                           Area Network                                                <15 km
                                                                                                                                  802.20 (proposed)


                    IEEE 802.16 Network                                    Wireless Metropolitan
                                                                           Area Network
                                                                                                                                      WMAN
                                                                                                                                       <5 km

                        Architecture                                                                                                  70 Mbit/s
                                                                                                                                      802.16a/e


                                                                           Wireless Local                                             WLAN
                                                                           Area Network                                                <100 m
                                                                                                                                     11-54 Mbit/s
                                                                                                                                    802.11a/b, e, g

                                                                           Wireless Personal                                          WPAN
                                                                           Area Network                                                 <10 m
                                                                                                                                       ~1 Mbit/s
                                                                                                                                  802.15.1 (Bluetooth)
                                                                                                                                   802.15.3 (UWB)
                                                                                                                                   802.15.4 (ZigBee)




                          Peak Data Rate                                                Spectrum Allocations
                                                    802.20
                                                                                                                      802.15.3a
                                                                                        802.15.1                        UWB
                                                                                       Bluetooth                       3.1-10.6
                                                                                          2.4
             Mobile                                                                                                                                            802.16
           (Vehicular)                                                                                      802.11 a, e                                        LMDS
                                                                                       802.11 b, g            Wi-Fi                                            28-29
                                                     802.16e                             Wi-Fi                  5.0
                                                                                           2.4
Mobility




           Pedestrian                                                           2GHz                           5GHz                11GHz                        29GHz
                                                         802.16a
           (Nomadic)
                                                        (WiMAX)


              Fixed               802.15.1           802.11    802.15.3a
           (Stationary)         (Bluetooth)         (WLAN)      (UWB)
                                                                                             802.16a, e      802.16a, e                                  Licensed
                                                                                              WiMAX           WiMAX
                                 0.1          1.0         10         100                       2-11             5.8                                      Unlicensed
                                                                                               Licensed &
                                                                                               Unlicensed
                          Peak Data Rate per User (Mbits/second)
     802.16 Standards History
 • First standard based on proprietary implementations of DOCSIS/HFC
                                                                                                 IEEE 802.16 Standards
 architecture in wireless domain
                                        • Original fixed wireless broadband air Interface   IEEE 802.16
                          802.16          for 10 – 66 GHz: Line-of-sight only, Point-to-
                        (Dec 2001)        Multi-Point applications                            Air interface on 10-66 GHz licensed bands
                                                                                              Light-of-sigh (LOS) transmission, point-to-point delivery
    802.16c
     (2002)                                                                                 IEEE 802.16a
                                        • Extension for 2-11 GHz: Targeted for non-
                         802.16a          line-of-sight, Point-to-Multi-Point                 Operations on 2-11 GHz licensed/non-licensed bands
 802.16 Amendment                         applications like “last mile” broadband access
                        (Jan 2003)                                                            Non-Light-of-sigh (NLOS) transmission, point-to-multipoint
WiMAX System Profiles
    10 - 66 GHz                                                                               delivery
                                        • Adds WiMAX System Profiles and Errata for
                                                                                            IEEE 802.16e
                         802.16REVd       2-11 GHz                                            Operation on 2-6 GHz licensed bands
                        (802.16-2004)
                          (Oct 2004)                                                          Support mobility
                                                                                            Promoted by WiMAX (World-wide Interoperability for
                                        • MAC/PHY Enhancements to support
                                                                                            Microwave Access)
                         802.16e          subscribers moving at vehicular speeds
                        (802.16-2005)
                          (Dec 2005)




              IEEE 802.16 Standards                                                            IEEE 802.16 Applications
                                                                                            Provide broadband Internet access with
                                                                                            transmission rates over >2 Mb/s
                                                                                            Replace DSL or cable
                                                                                               DSL can deliver up to 6 Mb/s at distances up
                                                                                              to 18,000 feet
                                                                                               IEEE 802.16 can deliver up to 120 Mb/s at
                                                                                              distances up to 30 km
                                                                                            Provide local multipoint distributed
                                                                                            services (LMDS)
           IEEE 802.16 Applications                                                             IEEE 802.16 Features
                                                                                           Use wireless links with microwave or millimeter
                                                                                           wave radios
                                                                                           Use licensed spectrum
                                                                                           Are metropolitan in scale
                                                                                           Provide public network service to fee-paying
                                                                                           customers
                                                                                           Use point-to-multipoint architecture with
                                                                                           stationary rooftop or tower-mounted antennas
                                                                                             Antenna with a variety of radiation patterns are used
                                                                                             (e.g., directional or Omni-directional)
                                                                                           Provide broadband and QoS guarantee data
                                                                                           transmissions




                  WLAN vs. WMAN                                                                  IEEE 802.16 Example
                           WLAN                                  WMAN
Typical max.
               Inferior to 100 m               12 ~ 15 km (LOS), 1~2 km (NLOS)
coverage
                                               For NLOS environments (2-11 GHz
Optimisation   For indoor short range spaces   band). Supports advanced antenna
                                               techniques

               LAN application. The number     Efficient support of hundreds of SSs with
               of users can vary between one   a limited number of users per SS.
Scalability
               to several tens, with a         Flexible bandwidth channels ranging 1.5-
               subscriber per CPE              20 MHz.

               Maximum spectral efficiency
                                               Maximum spectral efficiency 5 b/s/Hz.
Bit Rate       2,7 b/s/Hz.
                                               100 Mb/s in 20 MHz. channels
               54 Mb/s in 20 MHz channels.
                                               Native MAC QoS support.
QoS            Without QoS support
                                               Service differentiation levels
IEEE 802.16 Network Architecture          IEEE 802.16 Network Architecture




                                             BS: base station         RS: relay station
                                             SS: subscriber station   TE: terminal equipment




IEEE 802.16 Network Architecture           Components and Data Path
IEEE 802.16 specifies the air interface   IEEE 802.16 architecture consists of two
(PHY and MAC)between STS and BTS          kinds of fixed (non-mobile) stations
                                            Subscriber stations (SS)
                                            Base station (BS)
                                          The communication path between SS and
                                          BS has two directions
                                            Uplink (from SS to BS)
                                            Downlink (from BS to SS)
      Protocol Architecture                              Protocol Architecture
                                                  Physical and transmission layer functions:
                                                    Encoding/decoding of signals
                                                    Preamble generation/removal
                                                    Bit transmission/reception
                                                  Medium access control layer functions:
                                                    On transmission, assemble data into a frame with
                                                    address and error detection fields
                                                    On reception, disassemble frame, and perform
                                                    address recognition and error detection
                                                    Govern access to the wireless transmission medium




      Protocol Architecture                        IEEE 802.16 Bear Services
Convergence layer functions:                      Digital audio/video multicast: one-way
                                                  (broadcast radio and video) or two-way
   Encapsulate PDU framing of upper layers into   (teleconferencing)
  native 802.16 MAC/PHY frames                    Digital telephony: multiplexed digital telephone
   Map upper layer’s addresses into 802.16        streams
  addresses                                       ATM: transfer ATM cells
                                                  Internet protocol: transfer IP datagrams
   Translate upper layer QoS parameters into
                                                  Bridged LAN: transfer data between two LANs
  native 802.16 MAC format
                                                  Back-haul: provide wireless trunks for wireless
   Adapt time dependencies of upper layer         telephone base stations
  traffic into equivalent MAC service             Frame relay: transfer variable-length frames
Services and QoS Requirements
Circuit based
  Circuit-switching capability
  Connections are set up to subscribers across
  a core network
Variable packet
  IP and frame relay
  MPEG video
Fixed-length cell/packet
  For ATM




        Protocol Structure                                  MAC Protocol
                                                 Convergence sublayer
                                                   Handle the higher-layer protocols
                                                 Common part sublayer
                                                   Channel access, connection establishment
                                                   and maintenance, and QoS
                                                 Security sublayer
                                                   Authentication, secure key exchange, and
                                                   encryption
          MAC Protocol                          MAC PUD Transmissions




    Convergence Sublayer                          Convergence Sublayer
The service specific convergence sublayer    Functions:
                                               Classification, possible
(CS) provides any transformation or
                                               processing of higher-layer
mapping of external network data,              PDUs
received through the CS service access         Delivery to proper MAC SAP
point (SAP)                                    Receives CS PDUs from peer
Object : classifying external network        Two specifications:ATM and packet
                                               The higher layers will predominantly be ATM and
service data units (SDU) and associating       IEEE 802.3 (Ethernet)
them to the proper service flow identified     Each vendor can develop a difference convergence
by the connection identifier (CID)             sublayer
ATM Convergence Sublayer                         Packet Convergence Sublayer
ATM cells mapped to MAC frames                   used for all packet-based protocols,
Differentiates Virtual Path switched /           such as IPv4, IPv6, Ethernet, and VLAN
Virtual Channel switched ATM
                                                 Similar functions as ATM convergence
connections
Assigns channel ID (CID)                         sublayer, including PHS
Can perform Payload Header Suppression
(PHS)
   The process of suppressing the repetitive
  portion of payload headers at the sender and
  restoring the headers at the receiver




MAC Common Part Sublayer                         MAC Common Part Sublayer
Defines multiple-access mechanism                Connection-oriented protocol
Functions :system access, bandwidth                 Assign connection ID (A16-bit value that
allocation, connection establishment, and          identifies a connection to equivalent peers in
                                                   the MAC) to each service flow
connection maintenance
                                                 Each service flow (uniquely identified by a
                                                 SFID, 32-bit value) has it own QoS
                                                 parameter setting (latency, jitter, and
                                                 throughput)
                                                 BS grants the bandwidth allocation
          Security Sublayer                                Physical Layer Summary
The MAC security sublayer has two
component protocols:
  Encapsulation protocol for data encryption
    defines cryptographic suites i.e. pairings of data
    encryption and authentication algorithms
    the rules for applying those algorithms to a MAC
    payload
  Privacy key management (PKM)
    describes how the BS distributes keys to client SS




IEEE 802.16 Operation Bands                              IEEE 802.16 Operation Bands
Licensed bands between 10GHz~66GHz                       Licensed bands between 2GHz~11GHz
  Single-carrier PHY                                      Single and multi-carrier PHYs
  Frequency band is large (25~28MHz)
                                                          NLOS (non-line-of-sight) between transmit
    Allow data rate over 120Mb/s
  LOS (line-of-sight) between transmit and receive
                                                          and receive antennas
  antennas (trend to be blocked)                            received signal power can vary significantly
  Multipath is not an issue and the thermal noise and       Advanced power management technique
  interference are the main limited factors                Multipath can be significant and
  For outdoor setting                                     retransmission may be necessary
    Rain will increase the attenuation
IEEE 802.16 Operation Bands                          Adaptive PHY

Unlicensed bands between 2GHz~11GHz
  Physical characteristics are the same as
 above
  Other users may cause interferences and
 regulations limit the output power
   Dynamic frequency selection and power
   management



                                             (burst-by-burst adaptivity not shown)

				
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posted:7/11/2010
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Description: Wi-MAX (ie 802.16) technology since 2001 began to develop, now began to appear on the market related products, it is within 30 miles with the most wired LAN provides the same data transfer rate. This technology is considered a large number of broadband connections will be introduced to remote areas or to more decentralized communication covers enterprise and campus area method.