Overview of IEEE 802.16 / WiMAX

1
Overview ofIEEE 802.16 / WiMAX

• Presented by
• Dr. Sim Moh Lim
• mlsim2003_at_gmail.com

2
Agenda

• Part 1 Overview of WiMax (2h)
• Overview of the WiMax.
• History Evolution
• Spectrum
• Network architectures
• Current status and future trend

3
Overview
4
WIMAX / IEEE 802.16

• WIMAX stands for Worldwide Interoperability for
  Microwave Access as defined by WiMax Forum

• WiMAX networks refer to broadband wireless
  networks that are based on the IEEE 802.16
  standard, which ensures compatibility and
  interoperability between broadband wireless
  access equipment
• The IEEE 802.16 standards define how wireless
  traffics move between subscriber equipment and
  core networks

Source SHASHI JAKKU
5
WIMAX System General Features

• Subsystems
• A WiMAX tower
• similar in concept to a cell-phone tower - A
  single WiMAX tower can provide coverage to a very
  large area as big as 8,000 square km.
• A WiMAX client terminal
• The terminal receiver and antenna could be a
  small box or Personal Computer Memory card, or
  they could be built into a laptop the way WiFi
  access is today
• Range 50km from base station
• Speed 70 Megabits per second
• Frequency bands 2 to 11 and 10 to 66 (licensed
  and unlicensed bands)
• IEEE 802.16 standards define both MAC and PHY
  layers and allow multiple PHY layer specifications

6
IEEE 802.16 Specifications

• A family of standards for broadband wireless
  access

• 802.16a
• Uses the licensed frequencies from 2 to 11 GHz
  supports Mesh network
• 802.16b
• Increase spectrum to 5 and 6 GHz
• Provides QoS( for real time voice and video
  service)
• 802.16c
• Spectrum from 10 to 66GHz

Source SHASHI JAKKU

• 802.16d (d abc)
• Improvement and fixes for 802.16a
• 802.16e-2005
• Addresses on Mobile
• Enable high-speed signal handoffs necessary for
  communication with users moving at vehicular
  speeds

7
802.16e Compatibility with 16d

• 802.16e is the mobile extension from 802.16
• Modification in PHY from OFDM to Scalable OFDMA
• Modification in MAC for security, handoff,
  roaming, resource management

Service Specific Convergence Sub Layer
Packet Classifier
Header Suppression
IP
Ethernet
ATM
MAC Common Part Security Sub Layers
Bandwidth Management
Connection Management
PDU Generation
PDU Reassembly
Net Entry
Security/Privacy Key, AES, EAP
Power Mgnt Sleep/Idle
PHY Burst Scheduling
ARQ
Handoff
PHY Layer
OFDMA 2-11GHz 2048FFT
SC 10-66GHz
SCa 2-11GHz
OFDM 2-11GHz 256FFT
OFDMA 2-11GHz 128, 256,
512,1024, 2048
802.16d
802.16e
Source BeyondSpot Technology
8
Orthogonal Frequency Division Multiplexing (OFDM)

• Multiplexing technique that divides the channel
  into multiple orthogonal subchannels
• Input data stream is divided into several
  substreams of a lower data rate (increased symbol
  duration) and each substream is modulated and
  simultaneously transmitted on a separate
  subchannel with carrier orthogonal to each other
• High spectral efficiency, resilient to
  interference, and low multi-path distortion

FDM
OFDM

• OFDM is more spectral efficient as compared to
  FDM (allows more transmission channels)

9
WiMAX Forum

• Is an industry group founded in April 2001
• Consists of services providers, manufacturers,
  and related companies that have joined together
  to promote the family of technologies based upon
  the IEEE 802.16 standard
• Ensure interoperability of IEEE 802.16 and other
  interoperable (ETSI HiperMAN) systems
• Equivalent in purpose to Wi-Fi Alliance for IEEE
  802.11
• Develop Conformance Test Specifications
• Host interoperability events
• Provide WiMAX-Certified stamp of approval

10
Players in WiMAX Forum

• WiMAX Forum has gt500 members (530 as at 26/11/08)
• WiMAX members represent over 75 of current 2-11
  GHz BWA equipment sales!

And a lot more..
Source WiMAx Forum
11
WiMAX and IEEE 802.16

• WiMAX is a subset of IEEE 802.16
• No new features can be added
• Mandatory features in 802.16 are mandatory in
  WiMAX, if included
• Optional features in 802.16 may be optional,
  mandatory or not included

Source WiMAx Forum
12
MODES OF OPERATION

• WiMax can provide 2 forms of wireless service
• Non-LOS
• Wi-Fi sort of service, where a small antenna on a
  computer connects to the tower.
• Uses lower frequency range (2 to 11 GHz).
• LOS
• where a fixed antenna points straight at the
  WiMax tower from a rooftop or pole.
• The LOS connection is stronger and more stable
  higher throughput.
• Uses higher frequencies reaching a possible 66
  GHz.
• Through stronger LOS antennas, higher range can
  be achieved up to 50km radius.

13
Broadband Usage Scenarios

• Fixed wireless access (FWA)
• Wireless access application in which the
  location of the end-user termination and the
  network access point to be connected to
  the end-user are fixed.
• Backhaul for business
• Consumer last mile
• Nomadic wireless access (NWA)
• Wireless access application in which the location
  of the end-user termination may be in different
  places but it must be stationary while in use.
• Mobile wireless access (MWA)
• Wireless access application in which the location
  of the end-user termination is mobile.

Source WiMAx Forum
14
Types of access supported by WiMax
Source WiMax Forum
15
History Evolution
16
Why (earlier) BWA solutions have not taken off?

• Wireless Solutions Before WiMax
• Proprietary, vertical solutions
• No volume silicon market lack economies of
  scale
• Lack of global spectrum

Economies of scale as WiMax is an open standard
solution
Source WiMAx Forum
17
802.16 Standard History
2008
530
2006
Membership
802.16-2004 Fixed Broadband Wireless Standard
(Revised Covers lt11 GHz NLOS 10-66 GHz LOS
Systems)
343 members
2005
802.16e Combined Fixed and Mobile Amendment
for lt11 GHz Licensed Systems (Formally
approved in December 2005)
802.16c System Profiles for 10-66 GHz LOS
Systems(Inactive)
2004
55 members
65 members
802.16a Fixed Broadband Wireless Standard for
2-11 GHz Non-LOS Systems(Inactive)
802.16 Fixed Broadband Wireless Standard for
10-66 GHz LOS Systems(Inactive)
IEEE 802.16 Working Group Started
Time
Source Intel WiMax Forum
18
WiMax Spectrum
19
Global spectrum bands

• WiMax Forum is focusing on 3 spectrum bands for
  global deployment
• Unlicensed 5 GHz
• Includes bands between 5.25 and 5.85 GHz. In the
  upper 5 GHz band (5.725 5.850 GHz) many
  countries allow higher power output (4 Watts)
  that makes it attractive for WiMax applications.
• Unlicensed fixed outdoor services
• Licensed 3.5 GHz
• Bands between 3.4 and 3.6 GHz have been allocated
  for BWA in majority of countries.
• Explicitly allow Nomadic use in Fixed Wireless
  spectrum to support indoor modems and laptops
• Licensed 2.5 GHz
• The bands between 2.5 and 2.6 GHz have been
  allocated in the US, Mexico, Brazil and in some
  SEA countries. In US this spectrum is licensed
  for MDS and ITFS.
• New mobile services model and can address the
  broadband digital divide.

20
Licensed vs. License-Exempt Solutions
Licensed Solution License-Exempt Solution
FDD TDD
Better QoS Fast Rollout
Better NLOS reception at lower frequencies Lower Costs
Higher barriers for entrance More worldwide options
21

• WiMax Network Architectures

22
Wimax Network System Architecture
CSN Connectivity Service Network ASN Access
Service Network NSP Network Service
Provider NAP Network Access Provider HA Home
Agent, FA Foreign Agent AAA Authentication,
Authorization and Accounting
23
802.16 Network Architectures

• Point-to-Point (P2P) Architecture
• BS to BS
• P2MP Architecture
• BS serves several Subscriber Stations (SS)
• Provides SS with first mile access to Public
  Networks
• Mesh Architecture
• Optional architecture for WiMAX

Source SHASHI JAKKU
24
Key Goals for Network Architecture

• Should support a common evolution path from fixed
  to portable to mobile
• Support of IP infrastructure and a single
  topology to handle both packet voice and packet
  data efficiently
• Should handle IP multicast to the cell-edge for
  efficient operations
• Network Architecture should allow
• Lower Latency
• Higher data throughput
• Future Investment Protection
• Support Radio Evolution and/or multiple radio
  types
• Build a mobile device model and network
  architecture that is much less expensive

25
Current Future
26
Current Status

• More Than 350 Operator Trials and Deployments in
  65 countries!
• List of operators
• http//en.wikipedia.org/wiki/List_of_Deployed_WiMA
  X_networks

Source Intel, the WiMAX Forum
27
Current Status - Malaysia

• Existing fixed wireless BB licensed operators in
  WiMax bands
• 2.5 GHz (TM, Airzed, AtlasOne, EB Tech, Jaring
  Comm, TTDotCom, Maxis)
• 3.5 GHz (Airzed, Maxis, Nasioncom, TM, EB Tech,
  AtlasOne)
• 4 new players awarded 2.3GHz WiMax licenses,
  March 2007
• Asiaspace 2300 2330 (Peninsular)
• Bizsurf (50 assoc of YRL e-solution) 2330
  2360 (Peninsular)
• MIB (55 sub of Green Packet) 2360 2390
  (Peninsular)
• Aug 08 Packet One Networks launched its WiMax
  service in Klang Valley. Used Alcatel-Lucent
  equipment.
• 1.2Mbps (RM99) 2.4Mbps (RM229)
• Redtone-CNX 2375-2400 (East Msia)
• Aug 08 Redtone launched its WiMax network in
  Kota Kinabalu. Used Motorola equipment.

28
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.

29
Wireless Broadband Evolution to 4G

• Mobile
• Broadband
• 4G
• OFDM Based,
• MIMO, All-IP
• Core

Cellular
1G
LTE (2009)
2G
3G, HSDPA, HSUPA, HSPA
LTE advanced
Broadband Wireless
802.16e
802.16d
802.16m
802.16 REV 2 (2009)
802.11a/b/g
802.11n (2009)
Wireless LAN
30
Pre-4G
Source Wikipedia
31
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

32
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).

33
Thank You
34
Backup Slides
35
HiperMan (High Performance Radio Metropolitan
Area Network)

• a standard created by the European
  Telecommunications Standards Institute (ETSI)
  Broadband Radio Access Networks (BRAN) group
• to provide a wireless network communication in
  the 2 - 11 GHz bands across Europe and other
  countries which follow the ETSI standard.
• HiperMAN is a European alternative to WiMAX (or
  the IEEE 802.16 standard) and the Korean
  technology WiBro.

36
Flash-OFDM(Fast Low-latency Access with Seamless
Handoff Orthogonal Frequency Division
Multiplexing)

• Proprietary packet-switched broadband cellular
  technology developed and marketed by Flarion.
• Spinoff of Lucent Technologies
• Qualcomm bought over Flarion in 2005
• Physical layer is based on OFDM
• Uses fast hopping across all tones in a
  pseudorandom predetermined pattern (spread
  spectrum)
• Frequency reuse is 1
• Different BSs use different hopping patterns
• Link layer uses local (as opposed to end-to-end)
  feedback to create a very reliable link from an
  unreliable wireless channel, with very low
  delays.
• Services available in
• Finland, Slovakia, Germany, Virginia, Ireland,
  etc.

37
iBurst (or HC-SDMA, High Capacity Spatial
Division Multiple Access)

• a wireless broadband technology developed by
  ArrayComm.
• It optimizes the use of its bandwidth with the
  help of smart antennas.
• Kyocera is the leading manufacturer of iBurst
  devices.
• Standardized in
• ANSI HC-SDMA. ITU-R M.1801 Recommendation ,
  IEEE802.20 625k-MC mode for enhanced iBurst
  technology
• commercially available in eleven countries
• Australia, South Africa, Azerbaijan, Norway,
  Ireland, Canada, Malaysia (iZZinet at Klang
  Valley), Lebanon, Kenya, Ghana, Mozambique, UK
  and USA.

38
Feature 3GPP LTE Source 3GPP RAN1 3GPP2 AIE Source Qualcomm 802.16m/Mobile WiMAX R2
Duplexing Modes TDD, FDD TDD, FDD TDD, FDD
Channel Bandwidths 1.25, 1.6, 2.5, 5, 10, 15, 20 MHz 1.25 to 20 MHz 5, 10, 20, 40 MHz
Peak Data Rates (per sector _at_ 20 MHz) DL 288 (4x4) UL 98 (2x4) DL 250 Mbps (4x4) UL 100 Mbps (4x4) DL gt 350 Mbps (4x4) UL gt 200 Mbps (2x4)
Mobility Up to 350 km/hr Up to 250 km/hr (350 km/hr per SRD) Up to 350 km/hr
Latency Link-Layer Access lt5 ms Handoff lt50ms Link-Layer Access lt10ms Handoff lt20ms Link-Layer Access lt10ms Handoff lt20ms
MIMO Configuration DL 2x2, 2x4, 4x2, 4x4 MIMO UL 1x2, 1x4, 2x2, 2x4 MIMO DL 2x2, 2x4, 4x2, 4x4 MIMO UL 1x2, 1x4, 2x2, 2x4 MIMO DL 2x2, 2x4, 4x2, 4x4 MIMO UL 1x2, 1x4, 2x2, 2x4 MIMO
Average Sector Throughput _at_ 20 MHz TDD (DLUL21) DL 32 Mbps UL 6 Mbps DL 32 Mbps UL 7.1 Mbps DL gt 40 Mbps UL gt 12 Mbps
Spectral efficiency (per sector) Peak DL 14.4 bps/Hz (4x4) UL 4.8 bps/Hz (2x4) Sustained DL 2.4 bps/Hz UL 0.9 bps/Hz Peak DL 13 bps/Hz (4x4) UL 5 bps/Hz (4x4) Sustained DL 2.3 bps/Hz UL 1.0 bps/Hz Peak DL gt 20 bps/Hz (4x4) UL gt 10 bps/Hz (2x4) Sustained DL gt 3 bps/Hz UL gt 1.5 bps/Hz
Coverage (km) 5/30/100 km (Optimal performance at 5km) 5/10/30/100 km 1/5/30 km
Number of VoIP Active Users gt 80 users/sector/ FDD MHz gt 64 user/sector/FDD MHz (100 per 3GPP2 SRD) gt 100 users/sector/FDD MHz gt 50 users/sector/TDD MHz
Source Intel
39
Major ? ?

• Advantages
• Fresh design meant for outdoor BWA
• Multipath advantages
• Spectral efficiency
• Global harmonization

• Issues
• Regulatory difficulty
• Power constraint
• High layer integration
• Market and time competition
• Global spectrum availability

40
? 802.16 and HiperMAN Designed from Ground Up
for the Outdoors

• Higher throughput at longer ranges (up to 50 km)
• Better bits/second/Hz at longer ranges
• Scalable system capacity
• Easy addition of channels maximizes cell capacity
• Flexible channel bandwidths accommodate
  allocations
• Coverage
• Standards-based approach to advanced techniques
  (mesh, beam-forming, MIMO) to improve
  non-line-of-sight performance
• Quality of Service
• Connection oriented MAC supports voice and video
• Differentiated service levels E1/T1 for
  business best effort for residential
• Cost Investment Risk
• Interoperable equipment lets operators purchase
  equipment from more than one vendor
  WiMAX-Certified
• A stable, standards-based platform improves OpEx
  by sparking innovation at the network management
  layer, antenna layer elsewhere

41
? Advantages in Multipath

• OFDMA carries advantages in Multipath
• OFDMA select subcarriers with less channel
  degradation, prevent wasting system resource
  (power or throughput ) gt achieving higher system
  capacity.

Frequency selective fading due to multipath
Source BeyondSpot Technology
42
? Spectral Efficiency Wins

• Spectrum efficiency is an important factor for
  data service
• The scarce of available (or useful) spectrum
  makes efficiency a key factor to approve spectrum
  and the success of business model.
• Regulatory bodies shall recycle spectrum for
  existing systems with low spectral efficiency.
• Future systems with high spectrum re-use
  advantages or higher spectral efficiency shall
  have favored allocation during application.

• 2.5G TDMA Very limited data rate and low
  spectral efficiency (1.0-1.5 bps/Hz)

• 3G WCDMA Reasonable data rate, range, and
  mobility, improved spectral efficiency
  (1.5-2.5 bps/Hz)

• WiMAXOFDMA, Up to 2048FFT much improved range
  and mobility, potential for best spectral
  efficiency (3-4 bps/Hz)

• WiFi OFDM 64FFT, Reasonable data rate, limited
  range and mobility, improved spectral efficiency
  (2-3 bps/Hz)

Source BeyondSpot Technology
43
? Global Harmonization

• WiMAX has global harmonization
• WiMAX forum pushes harmonization between IEEE and
  ETSI there is only one WiMAX standard (ETSI has
  not fully adopted Mobile WiMAX yet)
• WiMAX share one MAC for all, fixed, portable, and
  mobile
• 3G breaks into WCDMA (3GPP), CDMA2000 (3GPP2),
  and more
• Among WCDMA, venders has their own proprietary
  modes.
• China has TDS-CDMA, US has UWC-136, and Japan has
  DoCoMo 3G

44
? Regulatory Difficulty

• VoIP over WiMAX has no obligation to secure QoS
• From architecture point of View VoIP challenges
  Traditional Telecom Regulatory Model. Is it an
  application or a telecomm service?
• When voice is no longer consider as
  telecommunication service, it is not bounded for
  availability, emergency service (911), or voice
  quality of service
• It is a pure low cost application, not a telecom
  service

• VoIP Can Not Address
• 99.999 availability
• The high quality of voice support as 3G
• The same level of robustness as circuit
• The same level of QoS as circuit

3G vs WiMax
45
? Power and RF Constraint

• Battery Life Challenge
• WiMAX standard was targeted to long range (high
  power), fixed (non-battery based), or portability
  (recharged daily), not mobility non-e.
• Higher data rate demands higher power
  transmission battery technology shows difficulty
  to catch up with the such demand.
• Power consumption of WiMAX device could be a
  major problem.

• 802.16s Effort in Power/RF
• Power-Saving mode and Scalable OFDMA are added to
  802.16e
• But higher FFT has more severe PAPR (peak to
  average power ratio)
• Challenge the RF design for WiMAX

Source BeyondSpot Technology
46
? Hi Layer Protocol Integration

• High Layer mobility is a challenge
• IEEE 802.16 by its mandate only defines protocol
  stacks in the PHY and MAC layer, 802.16e defines
  mobility support for MAC and PHY only
• Lack of network layer mobility completion
• WiMAX Forum is supposed to cover network
  mobility, but
• WiMAX forum has weak experience in end-to-end
  protocol stack development
• WiMAX is a pure industry ad-hoc group, like WiFi,
  which may not be the appropriate place to deal
  with Network Mobility standards
• Integration with legacy network requires support
  from the carriers

Source BeyondSpot Technology
47
? Market Time Competition

• WiMAX has risks too!
• Mobile WiMAX market is squeezed by both 3G, Flash
  OFDM, and WiFi.
• 802.11e, 11r, and 11n are enhancing QoS,
  handover, and throughput.
• HSDPA (of 3G) shorten the gap with WiMAX in
  throughput.
• Flash OFDM (by Flarion) has demonstrated
  end-to-end solution.

• Market takes time!
• Markets takes time to mature most new services
  will follow the letter N curve as below
• Fixed WiMAX technology is far from mass adoption,
  mobile WiMAX would take even longer

WiMAX Marketing Guy
Source BeyondSpot Technology
48
? Global Spectrum Availability

• Lack of Spectrum
• most licensed spectrum for broadband are either
  for fix services or for 3G
• hard to use license-exempt band to provide QoS
  guarantee mobile services

5.725 - 5.825 GHz (U-NII) or 5.725-5.850 GHz (ISM)
2.4 - 2.485 GHz (WLAN, Indoor Only)
3.5GHz (WLL) License bands
5.4 - 5.725 GHz (RLAN, Europe)
2.5-2.6GHz MDS, MMDS License bands )
5.25 - 5.35 GHz (U-NII, Outdoor/Indoor)
Source WiMAx Forum