3. INTRODUCTION
WiMAX:
“Worldwide Interoperability for Microwave Access”
supports point to multi-point (PMP) broadband wireless
access.
WiMAX is basically a new shorthand term for IEEE
Standard 802.16.
The IEEE wireless standard has a range of up to 30
miles or 50 kilometers.
4. WiMAX COVERAGE
WiMAX coverage is approximately 40 Mbit/s and is going
to touch 1 Gbit/s for fixed users in the near future.
Similarly, fixed users can access WiMAX and it ranges 50
km or 30 miles.
The case for the mobile user is different. It could not go to
that extent as stationary customers.
For mobile users the WiMax coverage is 5-15 km or 3-10
miles.
5. EVOLUTION OF IEEE 802.16
STANDARDS
• Evolution of IEEE family of standard for BWA
The standard provides secification for PHY and MAC layer
IEEE 802.16-2001
ᴥ fixed BWA access in a point-to-point (PTP) topology.
ᴥ Single carrier modulation
ᴥ 10-66 GHz frequency range
ᴥ Connection oriented
6. 6
EVOLUTION contd..
IEEE 802.16a
ᴥ Added physical layer support for 2-11 GHz
ᴥ NLOS operation becomes possible
ᴥ OFDM included as an alternative to single carrier modulation
IEEE 802.16-2004
ᴥ 2-11 GHZ frequency range
ᴥ 256 subcarriers OFDM Technique
ᴥ Fixed and Nomadic access
IEEE 802.16e
ᴥ Scalable OFDMA
ᴥ Mobile BWA
9. SAP: Service Access Point
PDU: Protocol Data Unit
Accept, perform classification, process higher PDUs
Deliver CS PDU to MAC SAP
Receive CS PDUs from the peer entity
System access, bandwidth
allocation
connection establishment,
connection maintenance
Authentication, security
key exchange,
encryption
IEEE Std 802.16 protoco
Multiple specifications
each appropriate to
frequency range (ex:
802.16.1 10-66GHz up to
134Mbit/s) and
application
10. IEEE 802.16 SPECIFICATIONS
IEEE 802.16 Protocol Stack
MAC Layer
Service specific convergence Sublayer(CS)
-MAC CS receives higher level data
-provides transformation and mapping into MAC SDU
-ATM CS and packet CS
MAC Common Part Sublayer (CPS)
- System access, bandwidth allocation, connection
management
-QoS provisioning
Privacy Sublayer
-Authentication, secure key exchange, encryption
PHY Layer
-Four different physical layer specifications
-SC, SCa, OFDM, OFDMA
Service-Specific
Convergence Sublayer (CS)
MAC Common Part
Sublayer (MAC CPS)
Security Sublayer
Physical Layer (PHY)
CS SAP
PHY SAP
MAC SAP
Data /Control Plane
P
H
Y
M
A
C
Scope of standard
Management Entity
Service Specific CS
Management Entity
MAC CPS
Security Sublayer
Management Entity
PHY
Management Plane
11. IEEE 802.16 SPECIFICATIONS
Cont. .
Network Architecture and Deployment Topology
Architecture
Resembled to cellular networks
Each cell consists of a BS and one or
more SS
BS provides connectivity to core network
Topology
Point to point (PTP)
Point to multi point (PTM)
Mesh
BS
SSs
BS
SSs
BS
SSs
Core Network
14. ISP PoPWire line or Wireless
backhaul
WiMAX Base Station
WiMAX point-to-multipoint
Homes with outdoor/indoor
WiMAX receiver
POINT TO
MULTIPOI
NT
APPLICAT
ION
15. NSHIP WITH OTHER WIRELESS TECHN
3G Mobile-Fi Wi-Fi WiMAX
Max. Speed 2 Mbps 16 Mbps 54 Mbps 100 Mbps
Coverage Several Miles Several Miles 300 feet 50 miles
Airwave Licensed Licensed Unlicensed Either
Advantages Range,
Mobility
Speed,
Mobility
Speed, Price Speed, Range
Disadvantages Slow,
Expensive
High Price Short Range Interference
issues
18. DRAWBACKS
• Line-of-Sight is required for long distance (5-30 mile)
connections.
• Heavy rains can disrupt the service.
• Other wireless electronics in the vicinity can interfere
with the WiMAX connection and cause a reduction in
data throughput or even a total disconnect.
• Network complex security issue.
• Not many areas have 4G service yet.
19. APPLICATIONS
Cellular Backhaul
- hotspots, PTP back haul
Residential Broadband
-fill the gaps in cable and dsl coverage
Underserved Areas
-rural areas
Always Best Connected
- roaming
21. CONCLUSION
WiMAX will no doubt be a viable alternative to DSL
and cable connections.
There more than 150 commercial trials WiMAX
network deployments have taken place worldwide.
In January 2006, Samsung revealed its WiMAX
enabled M8000 handset, which connects directly to
WiMAX base stations through 802.16e.
It will have stiff competition with already establish
broadband access technology (DSL & cable modem).
WiMAX is the future of ‘WBA technology’.
22. FUTURE SCOPE
• There are some good reasons for 4G development and a
variety of current and evolving technologies to make WiMAX
a reality.
23. FUTURE SCOPE
• MBWA is a technology developed by IEEE 802.20 for
true WBA or 4G.
• ‘Broadband Wireless’ internet access via hotspots on
hotels, airports, convention centre, coffee shops,
restaurants etc. is a fast growing trend.