1. BWA Operator Network Backbone
WiMAX Communication
BWA Operator Network Backbone
INTERNET
BACKBONE By
Saeed Mohi Adil Al-Shahrani
For
Dr. Landolsi, Mohamed

2. Worldwide Interoperability for Microwave Access
WiMAX
* WiMAX is a wireless digital communications system * WiMAX can provide broadband wireless access (BWA) * IEEE , " Wireless Metropolitan Area Networks (WMAN)“ * up to 30 miles (50 km) for fixed stations, and miles ( km) for mobile stations. 
* The word WiMAX stands for
Worldwide Interoperability for Microwave Access

3. Is WiMAX different from Wi-Fi?
WiMAX to Wi-Fi as Cellular to a Cordless Phone
Provide the service for large distance
Cordless
Cellular
Primarily consumer
License-exempt spectrum
Low cost
Mass market product
Low Power
Carrier Class
Licensed spectrum
Higher Cost
High Power
* Higher power increases coverage area

4. WiMAX Standard The IEEE standard 802.16 (WiMAX)
revised for 2-11GHz fixed ( a-2004) and 2-6GHz portable (802.16e) mobile wireless solutions.
WiMax uses Orthogonal Frequency Division Multiplexing (OFDM) for modulation in its physical layer, which bundles data over narrowband carriers transmitted in parallel at different frequencies.
OFDM makes WiMax scalable for a fluctuating user base, since the spectrum can be dynamically reallocated (range: MHz) with variations in the number of subscribers.
There are a number of challenges facing WiMax including:
RF interference and attenuation
Operator contention for infrastructure placement to maximize performance and reach
Government regulations, spectral licensing/usage management
Concerns with WiMax base station market growth due to bias towards voice networks (like GSM and UMTS)

5. WiMAX Standard
Orthogonal frequency-division multiplexing (OFDM), also sometimes called discrete multitone modulation (DMT),
complex modulation technique for transmission based upon the idea of frequency-division multiplexing (FDM) where each frequency channel is modulated with a simpler modulation. In OFDM the frequencies and modulation of FDM are arranged to be orthogonal with each other which almost eliminates the interference between channels
Orthogonal Frequency Division Multiple Access (OFDMA) is a multiple access scheme for OFDM systems. It works by assigning a subset of subcarriers to individual users.
OFDMA features
OFDMA is the “multi-user” version of OFDM
Each OFDMA user transmits symbols using sub-carriers that remain orthogonal to those of other users
More than one sub-carrier can be assigned to one user to support high rate applications
Allows simultaneous transmission from several users better spectral efficiency
Multiuser interference is introduced if there is frequency synchronization error
The term "OFDMA" is used in the mobility mode of IEEE WirelessMAN Air Interface standard, commonly referred to as WiMAX.

6. WiMAX Standard
cellular 3G is voice-centric while WiMax is data-centric.
WiMax can achieve data rates up to 75Mbps for fixed stations

7. WiMax Standards 802.16 802.16a 802.16-2004 802.16e-2005 Date Completed
December 2001
January 2003
June 2004
December 2005
Spectrum
10-66 GHz
< 11 GHz
< 6 GHz
Operation
LOS
Non-LOS
Non-LOS and Mobile
Bit Rate
Mbps
Up to 75 Mbps
Up to 15 Mbps
Cell Radius
1-3 miles
3-5 miles

8. Standards History
First standard based on proprietary implementations of DOCSIS/HFC architecture in wireless domain
802.16
(Dec 2001)
Original fixed wireless broadband air Interface for 10 – 66 GHz: Line-of-sight only, Point-to-Multi-Point applications
802.16c
(2002)
802.16a
(Jan 2003)
Extension for 2-11 GHz: Targeted for non-line-of-sight, Point-to-Multi-Point applications like “last mile” broadband access
802.16REVd ( )
(Oct 2004)
Adds WiMAX System Profiles and Errata for 2-11 GHz
802.16e
( )
(Dec 2005)
MAC/PHY Enhancements to support subscribers moving at vehicular speeds

9. WiMAX Standard The presence of two versions of WiMAX
WiMAX only supports fixed access, products are available.
802.16e WiMAX supports mobile and fixed access but products are still.
Vendors need to understand what demand there is for these two technologies in order to refine their product roadmaps and provide the service

10. IEEE Specifications
802.16a
use the licensed and license-exempt frequencies from 2 to 11Ghz
Support Mesh-Network
802.16b
Increase spectrum to 5 and 6GHz
Provide QoS (for real- time voice and video service)
802.16c
Represents a 10 to 66GHz system profile
802.16d
Improvement and fixes for a
802.16e
Addresses on Mobile
Enable high-speed signal handoffs necessary for communications with users moving at vehicular speeds

11. What are they aiming for?
BROADBAND WIRELESS ACCESS
802.16/a
Backhaul
WiFi
802.16
LOS to fixed outdoor antenna
802.16e
NLOS to MSS (laptop/PDA..)
WiMAX
Base Station
WiFi
WiFi
Fixed Wireless Access:
DSL to homes and business
802.16a
NLOS to fixed Indoor antenna
802.16a
NLOS to fixed outdoor antenna
MSS: Mobile Subscriber Station; LOS: Line of Sight; NLOS: Non Line of Sight

12. How WiMax Works WiMax can provide 2 forms of wireless service:
- Non-LOS 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, so it is able to send a lot of data with fewer errors. Uses higher frequencies, with ranges reaching a possible 66 GHz.
Freq. increases, so Peak of fingers (multipaths) decreases
Through stronger LOS antennas, WiMax transmitting stations would send data to WiMax enabled computers or routers set up within 30 (3,600 square miles of coverage) mile radius ~ 50 km.

13. WiMax is well suited to offer both fixed and mobile access

14. EXAMPLE SEIMENS

15. Siemens SkyMAX Base Station
SkyMAX – Forerunner in the WiMAX Arena SkyMAX BaseStation
Channel Size Software Configurable up to 14MHz
FDD and TDD Duplex scheme
Carrier-Grade redundancy
Flexible and Reliable
Software upgradeable to IEEE802.16e SOFDMA (Scalable OFDM Access)
Future Proof Platform
Siemens SkyMAX Base Station
High Scalability “Pay as you grow”
Triple Play services with guaranteed QoS
Scalable
Highest range, High Power system
Subchanneling and RX Diversity (in one ODU)
Highest Range

16. Integration in Back-end (e.g user Authentication charging/billing)
SkyMAX – Forerunner in the WiMAX Arena Fixed BWA Reference Architecture
Data
SkyMAX
Residential CPE
Back-end
User DB
CRM
Billing
Application Servers
Voice
Video
Air
Interface
Server Farm
WIP
Video
Public Internet
Data
Voice
End User
Access Gateway
SkyMAX
Business CPE
IP “Managed” Network
Voice Gateway
Voice
PSTN
Video
Data
SkyMAX
Basestation
GbE
End Users
User Equipment and
Applications
WiMAX (SkyMAX)
Radio Access:
BS and CPE
Backhauling and
Integration in Back-end (e.g user Authentication charging/billing)
Core Network

17. WiMAX Network

18. 802.16 Network Entry Scanning Ranging Registration
Scan for BS downlink channel
Synchronize with BS
Specifies channel parameters
Ranging
Set PHY parameters correctly
Establish the primary management channel (for negotiation, authentication, and key management)
Registration
Result in establishment of secondary management connection (for transfer of standard based management messages such as DHCP, TFTP )
Establishment of transport connection
MAC provides service for upper layers

19. Worldwide WiMAX Trials
Source: Intel estimates
>150
802.16
Planned Carrier Trials
2007
2006
2005
Worldwide WiMAX Trials

20. 4G Competitors
A generation is defined by the result of technology changes over a year time frame.
Thus, 4G would refer to whatever is deployed in the period, assuming 3G deployment spans the period. Typically, this means a new air-interface with higher data rates
Ideally, 4G would provide users with on demand high quality video and audio.
4G may use OFDM (Orthogonal Frequency Division Multiplexing), and also OFDMA (Orthogonal Frequency Division Multiple Access) to better allocate network resources to multiple users.
Unlike the 3G networks which are a jumble of circuit switched and packet switched networks, 4G will be based on packet switching only. This will allow low-latency data transmission.
According to a Visant Strategies study (quoted in Wireless Week on February 1st, 2006), there will be multiple competitors in this space (4G), and gave the following projections:
WiMAX million units by 2010
TD-SCDMA million subscribers (in China) by 2010
Flash-OFDM - 13 million subscribers in 2010
UMTS FDD - Valued at $2 billion in 2010

21. Next Wireless Fixed Mobile Convergence Example:
Korean will start the service by next year (WiBro)

22. Next Wireless
wireless broadband will emerge as the mainstream technology.
Data traffic is growing more (10 times) compared to the voice traffic
Consequence, the past concept of telephone networks, which also carry data might be replaced by the concept of data networks that also carry voice.
The cost for this service could be much lower than current high-speed Internet-subscription fees because the provider never had to run cables.

23. Thank you
Questions??
News about WiMAX