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Presented By:
L. SRINIVASA MURTHY.
III / IV B-Tech ECE
K.SASIDHAR.
III / IV B-Tech ECE
QIS COLLEGE OF ENGINEERING & TECHNOLOGY
VENGAMUKKALAPALEM”ONGOLE
PRAKASAM DISTRICT

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ABSTRACT:
The Presentation intended to review the advancements in Networking how they
find their application in different areas of communication.
Networking makes communication easy ,
Wireless Networking gives us Mobility.
WiMax has helped push the wireless communication scenario into hyperdrive.For many years
cables ruled the world. Optical fibers played a dominant role for its higher bit rates and faster
transmission. But the installation of cables caused a greater difficulty and thus led to wireless
access. The foremost of this is Bluetooth which can cover 9-10mts. Wi-Fi followed it having
coverage area of 91mts. No doubt, introduction of Wi-Fi wireless networks has proved a
revolutionary solution to last mile problem.
However, the standard's original limitations for data exchange rate and range, number of
channels, high cost of the infrastructure have not yet made it possible for Wi-Fi to become a
total threat to cellular networks on the one hand, and hard-wire networks, on the other. But
the mans continuous quest for even better technology despite the substantial advantages of
present technologies led to the introduction of new, more up-to-date standards for data
exchange rate i.e., WiMAX.
WiMax provides broadband communication in the area of over 49 km in range with the
bandwidth comparable to that for cable bands - up to 10 Mbit/s and higher. The WiMAX
technology allows operating in any conditions, including in the dense urban coverage, and
providing a high quality of communications and data transmission rate. It provided an
alternative solution to last mile problem by implementing broadband "last mile"
connections, deployment of wireless access point, arrangement of high-speed communication
among company branches and solution of other similar tasks. This paper presents WiMax
technology, its features, real time and coming application areas.
We are very happy to place this paper before the academic fraternity. Now it will be our
pleasure to receive the readerâ„¢s feedback. We feel such a feedback is vital to improving the
knowledge of an efficient engineer, thereby achieving its purpose.
Key words: Last mile, Bluetooth, WiMax , Wi-Fi.

INTRODUCTION:

The wireless revolution is underway, and devices based on radio technologies are
expected to become a significant market in the next several years. Mobile phones,
cordless phones, walkie-talkies, car door openers, and garage door openers are just a few
examples of radio devices that have already achieved widespread adoption in the
marketplace. Out of the past several years, innovations in wireless radio technology such as
Bluetooth,Wi-Fi (ieee-802.11b) and WiMax (ieee-802.16e) have captured our attention.
Some pitfalls in has led to the advent of wimax technology. WiMax offers some advantages
over WiFi, a similar wireless technology, in that it offers a greater range and is more
bandwidth-efficient. Ultimately, WiMax may be used to provide connectivity to entire cities,
and may be incorporated into laptops to give users an added measure of mobility.
WiMax requires a tower, similar to a cell phone tower, which is connected to the Internet
using a standard wired high-speed connection, such as a T3 line. But as opposed to a
traditional Internet Service Provider (ISP), which divides that bandwidth among customers
via wire, it uses a microwave page link to establish a connection.
Because WiMax does not depend on cables to connect each endpoint, deploying WiMax to
an entire high- rise, community or campus can be done in a matter of a couple days, saving
significant amounts of manpower.
WHY WIMAX?
The reason for pushing into WiMax technology is because of pitfalls of earlier technologies
i.e., Bluetooth and Wi-Fi.Lets see the comparisons and features of those two technologies.
BluetoothversusWiFi:

WHAT IS WIMAX?
WiMax (worldwide Interoperability for Microwave Access) is the recently approved IEEE
802.16 wireless metropolitan area network (MAN) standard for wireless access. WiMax is
the real wireless architecture by which the wireless access range can extended to 49.6Kms
compared with Wi-Fi 91mts and Bluetoothâ„¢s 9mts. WiMax 802.16 has a single carrier
modulation scheme that operates between 10GHz and 66GHz radio frequency and requires
line of sight towers for the connection to work. The new ratified 802.16a extension uses a
lower frequency range of 2GHz to 11GHz, and does not require line of sight towers. It also
boasts 70Mbps data transfer rate that can support thousands of users.

ARCHITECTURE OF WiMax:
The core components of a WiMax system are the subscriber station (SS) and the base station
(BS). A BS and one or more SSâ„¢s can form a cell with point to multipoint (P2MP) structure.
An 802.16 based system often uses fixed antenna at the subscriber station site. The antenna is
mounted on the roof. Provisions such as adaptive antenna systems and sub channel stations
are also supported by this system.
A BS typically uses either directional or omni directional antennas. A fixed SS typically uses
directional antenna while mobile or portable SS uses an omni directional antenna. Multiple
BSâ„¢s can be configured to form a cellular wireless network. The 802.16 standard also can be
used in a point to point topology with pairs of directional antennas. This increases the
effective range of the system compared to what can be achieved in the P2MP mode.

FUNDAMENTAL TECHNOLOGIES IN 802.16:

OFDM (Orthogonal Frequency Division Multiplexing):
It is fundamental technology in digitital TV. It transmits multiple signals simultaneously
across the wireless transmission paths within separate frequencies to avoid interference. It is
also supported in the WLAN standard. OFDM will almost certainly become dominant in all
wireless technologies.
ADAPTIVE MODULATION:
Many systems in the past decade have involved in the fixed modulation, offering a trade off
between higher order modulation for high data rates, but requiring optimal links or more
robust lower order that will only operate at low data rates. But 802.16 supports adaptive
modulation, balancing different data rates and page link quality, making most efficient use of
bandwidth.

FDD AND TDD:
The standard also supports both frequency and time division multiplexing to enable
interoperability with cellular and other wireless system. FDD has been widely deployed in
cellular telephony. It requires two channel pairs. One for transmission and other for reception,
with some frequency separation between them to migrate self- interference. TDD uses a single
channel for both upstream and downstream transmissions, dynamically allocating bandwidth
depending on traffic requirements.

FEATURES OF WIMAX:
The WiMAX standard has been developed with many objectives in mind. These are
summarized below:

1. Flexible Architechure:

Wimax supports several system architectures, including Point-to-Point, Point- to-Multipoint,
and ubiquitous coverage. The WiMAX MAC (Media Access Control) supports Point- to-
Multipoint and ubiquitous service by scheduling a time slot for each subscriber
station(SS).If there is only one SS in the network, the WIMAX Base Station (BS) will
communicate with the SS on a Point-to-Point basis. A BS in a Point-to-Point configuration
may
use
narrower
beam
antenna
to
cover
longer
distances.

2. High Security:
WiMAX supports AES (Advanced Encryption Standard) and 3DES (Triple DES, where
DES is the Data Encryption Standard). By encrypting the links between the BS and the SS,
WiMAX provides subscribers with privacy (against eavesdropping) and security across
the broadband wireless interface. Security also provides operators with strong protection
against theft of service. WiMAX also has built- in VLAN support, which provides
protection for data that is being transmitted by different users on the same BS.

3. Quick Deployment:
Compared with the deployment of wired solutions, WiMAX requires little or no external
plant construction. For example, excavation to support the trenching of cables is not
required. Operators that have obtained licenses to use one of the licensed bands, or that plan
to use one of the unlicensed bands, do not need to submit further applications to the
Government. Once the antenna and equipment are installed and powered, WiMAX is ready
for service. In most cases, deployment of WiMAX can be completed in a matter of hours,
compared with months for other solutions.
4. Multi-Level Service:
The manner in which QoS is delivered is generally based on the Service Level Agreement
(SLA) between the service provider and the end-user. Further, one service provider can
offer different SLAs to different subscribers, or even to different users on the same SS.
5. Interoperability:
WiMAX is based on international, vendor- neutral standards which make it easier for end-
users to transport and use their SS at different locations, or providers. Interoperability
protects the early investment of an with different service operator since it can select
equipment from different equipment vendors, and it will continue to drive the costs
of equipment down as a result of mass adoption.
6. Portability:
As with current cellular systems, once the WiMAX SS is powered up, it identifies itself,
determines the characteristics of the page link with the BS, as long as the SS is registered in the
system database, and then negotiates its transmission characteristics accordingly.
7. Mobility:
The IEEE 802.16e amendment has added key features in support of mobility.
Improvements have been made to the OFDM and OFDMA physical layers to support
devices and services in a mobile environment. These improvements, which include
Scaleable
OFDMA,
MIMO,
and
support
for
idle/sleep
mode
and
hand-off
will allow full mobility at speeds up to 160 km/hr. The WiMAX Forum-supported
standard has inherited OFDM's superior NLOS (Non-Line of Sight) performance and
multipath-resistant operation, making it highly suitable for the mobile environment.
8. Cost-effective:
WiMAX is based on an open, international standard. Mass adoption of the standard, and
the use of low-cost, mass-produced chipsets, will drive costs down dramatically, and the
resultant competitive pricing will provide considerable cost savings for service providers and
end-users

9. Wider Coverage:
WiMAX dynamically supports multiple modulation levels including BPSK, QPSK, 16-
QAM and 64-QAM. When equipped with a high-power amplifier and operating with a
low- level modulation (BPSK or QPSK, for example), WiMAX systems are able to cover a
large geographic area when the path between the BS and the SS is unobstructed.
10. Non-Line-of-Sight Operation:
NLOS usually refers to a radio path with its first Fresnel zone completely blocked.
WiMAX is based on OFDM technology, which has the inherent capability of
handling NLOS environments. This capability helps WIMAX products deliver broad
bandwidth in a NLOS environment, which other wireless product cannot do.

11. High Capacity:
Using higher modulation (64-QAM) and channel bandwidth (currently 7MHz, with
planned evolution towards the full bandwidth specified in the associated IEEE and ETSI
standards),WiMax
systems
can
provide
significant
bandwidth
to
end- users.

WIMAX ACCESS DEVICES:
This figure shows some of the different types of WiMax access devices. This diagram
shows that access devices include network termination units, internal radio modules,
network interface cards, PCMCIA cards, external boxes that connect to Ethernet or USB
sockets on communication devices.
WIMAX SYSTEMS:
This figure shows that WiMax systems may be use to provide point to point (PMP) or point
to multipoint (PMP) communication services and that WiMax systems can provide different
types of communication services (voice, data and video) from a common digital switching
system. This diagram also shows that WiMax system can be used to provide dedicated high-
speed data communication links or it may be used to provide broadband wireless service to
hundreds of users in relatively large geographic area.

APPLICATIONS:
There are many usage scenarios that can be addressed by WiMAX. The following are
some mobility usage applications of WiMAX.
1.Cellular Backhaul:
The market for cellular services is becoming more and more competitive. To stay in the
business, cellular operators are constantly looking for ways to reduce operating costs.
Backhaul costs for cellular operators represent a significant portion of their recurring
costs
WiMAX can provide Point-to-Point links of up to 30 miles (50 km), with data rates
capable of supporting multiple E1/T1s Cellular operators can therefore use WiMAX
equipment to backhaul Base Station traffic to their Network Operation and Switching
Centers, as shown below:
2. Banking Networks:
Large banks can connect branches and ATM sites to their
shown below. These banks are normally spread over a large area and need high security and
bandwidth to handle the traffic.

3. Offshore communication:
Oil and gas producers can use WiMAX equipment to provide communication links
from land-based facilities to oilrigs and platforms, to support remote operations,
security,
and
basic
communications.
Remote
operations
include
remote
troubleshooting of complex equipment problems, site monitoring, and database
access. WiMAX networks are quickly and easily deployed. The network can be set
up or redeployed in a matter of hours, if not minutes, even when oilrigs and platforms
are moved to other locations. wired solutions are not appropriate for this scenario,
because the facilities are offshore, and since oilrigs are temporarily located and
moved regularly within the oil or gas field.

4.EducationNetworks:
School boards can use WiMAX networks to connect schools and school board
offices within a district, as shown below. Some of the key requirements for a school
system are NLOS, high band- width (>15 Mbps), Point-to-Point and Point- to-
Multipoint capability, and a large coverage footprint

5. Public Safety:
Government public safety agencies, such as police, fire, and search and rescue, can
use WiMAX networks to support response to medical and other emergency situations, as
illustrated below:

6. Campus Connectivity:

Government agencies, large enterprises, industrial campuses, transportation hubs,
universities, and colleges, can use WiMAX networks to connect multiple locations, sites and
offices within their campus, as shown below. Campus systems require high data capacity,
low latency, a large coverage footprint, and high security:
Disadvantages of WiMax:
We have designed WiMax mainly for large distance communication. The main obstacle to
long distance communications are limitations on battery power and poor power efficiency
CHIPADVANCESHow can we overcome drawback?)
The main obstacles to long distance wireless communications are limitations on battery
power and poor power efficiency. Regulation keeps the power levels low and the range of
Wi-Fi signals short, to avoid the overcrowding of airwaves. But advances in DSP chips mean
that weak signals can be deciphered, lengthening the distance that is practical for
transmission, as well as improving distance and speed potential. Battery improvement is vital
to make a WiMax cell phone a practicality.Nokia is working on battery and handset chip
designs towards this end. Intel is increasingly involved in next generation battery and
processing power for mobile devices, including digital radios that can intelligently tune in to
the most efficient network like Cellular,Wi-Fi,Bluetooth,WiMax.

AT PRESENT:
At present we are using WiMax in different areas. The following are the real time
applications of WiMax technology.1. Interactive gaming.
2. VoIP, Video conference
3. Streaming media.

IN FUTURE:
In coming years WiMax also plays a vital role in
1.Information Technology
2.Media content download

CONCLUSION:
Within five years, we expect WiMax to be the dominant technology for wireless networking.
By that time it will be fully mobile, as well as providing low-cost, fixed broadband access
that will open up regions where internet access has no far not been practical.WiMax will be
the most significant technology in making wireless access ubiquitous and, as the free
spectrum is opened up, in creating a major shake-up of the traditional shape of the wireless
and mobile communications sector.

REFERENCES:
Information Technology magazine (oct 2006)
2)
IEEE magazines
intelsemiworks.com
houstuffworks.com