My Capstone Final Ppt

8/2/2019 My Capstone Final Ppt

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Submitted by

Sumit Kumar

Regd. No. : 10804016

B.tech (ECE) E38E1

RE38E1A12

Under the Guidance of

Er. Komal Arora

Dept. of ECE


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Introduction

Worldwide interoperability

Wi-max is the trade name of IEEE 802.16 standard

Goal of WIMAX

Infrastructure of Wi-MAX

Wi-max tower

Wi-max receiver


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Background

Wi-fi issues

Benefits Of Wi-MAX

Speed

Wireless

Broad coverage

Benefits to Service Providers

Benefits to Customers


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Uses


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What is Wi-MAX?

Specifications of Wi-MAX

Wi-MAX/Wi-Fi Synergies

Wi-MAX/Wi-Fi synergies enable integration of both wireless

technologies into notebooks and mobile devices


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Specifications of Wi-MAX


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Transmitter


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Reed-Solomon Encoder

Constructing a polynomial from the data symbols to be transmitted

Sending an oversampled version of the polynomial instead of the original

symbols


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Convolution encoding is a process of adding redundancy to asignal stream

A convolution encoder accepts messages of length k0 bits and

generates code words of N0 bits


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Puncturing Process

The process of systematically deleting bits from the output stream


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Scatter error bursts

Reduce the error concentration to be corrected

Implemented by using a two-dimensional array buffer


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Modulation scheme are used to map coded bits

The bits are mapped to a subcarrier amplitude and phase


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Downlink and uplink are composed using training sequences

All derived from frequency domain sequence

PSHORT, used for synchronization

The second OFDM symbol for channel estimation


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IEEE 802.16

Range- 30 miles from base station

Speed- 70 Megabits per second

Frequency bands- 2 to 11 and 10 to 66Defines both MAC and PHY layer


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802.16a

Uses the licensed frequencies from 2 to 11 GHz. Supports Mesh network

802.16b

Increase spectrum to 5 and 6 GHz. Provides Quos( for real time voice and video service)

802.16c

Represents a 10 to 66GHz.

802.16d

Improvement and fixes for 802.16a

802.16e

Addresses on Mobile. Enable high-speed signal handoffs necessary for communications

with users moving at vehicular speeds


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MAC (Data Link) Layer

MAC layer consists of three sub layers:

Service Specific Convergence Sub-layer (MAC CS)

The MAC Common Part Sub-layer (MAC CPS) and

The privacy sub-layer

Physical Layer

IEEE 802.16 specified a physical layer operating in the 10 to 66 GHz

range. 802.16a, updated in 2004 to 802.16-2004, added specifications for

the 2 to 11 GHz range.

802.16-2004 was updated by 802.16e-2005 in 2005 and uses scalable

orthogonal frequency-division multiple access (SOFDMA) as opposed to

the orthogonal frequency-division multiplexing (OFDM) version with 256

sub-carriers (of which 200 are used) in 802.16d.


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Scalability - The 802.16 standard supports flexible radio frequency (RF)channel bandwidths. The standard supports hundreds or even thousands of

users within one RF channel. As the number of subscribers grow the

spectrum can be reallocated with process of sectoring.

Quality of Service - Primary purpose of QOS feature is to define

transmission ordering and scheduling on the air interface.These featuresoften need to work in conjunction with mechanisms beyond the air interface

in order to provide end to end QoS.

Range It is Optimized for up to 50 Km and designed to handle many

users spread out over kilometres. Also it has been designed to tolerate

greater multi-path delay spread (signal reflections) up to 10.0 seconds.PHY and MAC designed with multi-mile range in mind.

Coverage - Standard supports mesh network topology and optimized for

outdoor NLOS performance.Also standard supports advanced antenna

techniques.


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Technologies using DSSS (802.11b, CDMA) and other wide

band technologies are very susceptible to multipath fading,

since the delay time can easily exceed the symbol duration,

which causes the symbols to completely overlap (ISI). The use

of several parallel sub-carriers for OFDMA enables muchlonger symbol duration, which makes the signal more robust to

multipath time dispersion


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This type of fading affects certain frequencies of a transmission and can result in

deep fading at certain frequencies. One reason this occurs is because of the wide

band nature of the signals. When a signal is reflected off a surface, different

frequencies will reflect in different ways.In Figure below, both CDMA (left) and OFDMA (right) experience selective

fading near the center of the band. With optimal channel coding and interleaving,

these errors can be corrected. CDMA tries to overcome this by spreading the

signal out and then equalizing the whole signal. OFDMA is therefore much more

resilient to frequency selective fading when compared to CDMA.


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Wi-MAX, more flexible and secure

Terminal authentication by exchanging certificates to prevent

rogue devices,

User authentication using the Extensible AuthenticationProtocol (EAP),

Data encryption using the Data Encryption Standard (DES) or

Advanced Encryption Standard (AES), both much more robust

than the Wireless Equivalent Privacy (WEP) initially used byWLAN. Furthermore, each service is encrypted with its own

security association and private keys.


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An important and very challenging function of the WiMAX system is thesupport of various advanced antenna techniques, provide high spectral

efficiency, capacity, system performance, and reliability:

Beam forming using smart antennas provides additional gain to bridge long

distances or to increase indoor coverage; it reduces inter-cell interference

and improves frequency reuse,

Transmit diversity and MIMO techniques using multiple antennas take

advantage of multipath reflections to improve reliability and capacity.

Wi-MAX technology can provide coverage in both LOS and NLOS

conditions. Furthermore, Wi-MAX has many optional features, such as

ARQ, sub-channeling, diversity, OFDM technology, adaptive modulation

and error correction. and space-time coding that will prove invaluable to

operators wishing to provide quality and performance that rivals wire line

technology.


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Advantages

Single station can serve hundreds of users.

Much faster deployment of new users comparing to wired networks.

Speed of 10 Mbps at 10 kilometers with line-of-site.

It is standardized, and same frequency equipment should work together.

It has the capacity to offer different types of services in one platformMany think that the tower becomes overloaded due to high number ofrequests from users but wi-max has an inner built algorithm which transfersthe user to another wi-max tower.

Wi-Max is a globally accepted, technically capable, and industry-widesupported standard.

The emergence of Wi-Max has opened up the solution to many of theproblems faced by Wi-Fi because, Wi-Max cover tens of miles unlike Wi-Fithat is restrictive to the surroundings and resources.

Through Wi-Max wireless networking is possible through longer distances.

Wi-Max can run in licensed and non licensed frequencies.

It has the capacity to offer different types of services in one platform.


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1) Line of sight is needed for more distant connections.

2) Bad weather conditions such as rain could interrupt the signal.

3) Other wireless equipment could cause interference.

4) Multiplied frequencies are used.

5) Wi-MAX is a very power-consuming technology and requires significant

electrical support.

6)High installation and operational cost.


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One can easily access the network at any place any time. It got its easilyand efficient accessibility in the basement.

Built for the future, Wi-MAX technology will allow one to connect in more

places, more often, without being restricted to hotspots.

Intel is providing advancements in wireless mobile technology for the

future of notebooks and a wide range of consumer devices.The IEEE 802.16 standard body members are working toward incremental

evolution, from fixed operation to portability and mobility.

IEEE 802.16f and IEEE 802.16g task groups are addressing the

management interfaces for fixed and mobile operation.

In a fully mobile scenario users may be moving while simultaneouslyengaging in a broadband data access or multimedia streaming session.


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The latest developments in the IEEE 802.16 group are driving a broadband wireless

access evolution, thanks to a standard with unique technical characteristics.

"Always Best Connected" experience.

The combination of these capabilities makes Wi-MAX attractive for a wide

diversity of people: fixed operators, mobile operators and wireless ISPs, but also for

many vertical markets and local authorities.

WLANs and 3G cellular networks are experiencing several difficulties for reaching

a complete mobile broadband access, bounded by factors such as bandwidth,

coverage area, or infrastructure costs.

In this context, Wi-MAX appears to fulfil these requirements, providing vehicular

mobility and high service areas and data rates.

This term paper is devoted to study the implementation of Wi-MAX system and

implementation of its transmitter and receiver through MATLAB software isachieved.


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THANKYOU..ANY QUERIES???

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