EE418 Wireless Communications Fall 2005 Team YMaxx

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EE-418 Wireless CommunicationsFall
2005Team YMaxx
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Team YMaxx

• Team Members
• Sam Anabtawi ECE
• Jermaine Lewis LEWISJ31
• Chintan Dalwadi CHINTAN
• Jaekia Fuqua JF8548
• Daphne Sanders SHARRELL

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Presentation Structure

• Introduction
• Protocol Architecture
• Standards
• Modulation
• Features
• Deployment
• Business
• Q A

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Introduction

• Worldwide Interoperability for Microwave Access
• A subset of IEEE 802.16
• Broadband MAN Technology

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Revisions
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802.16 Protocol Architecture

• Addresses transmission issues
• Higher level protocols are independent of network
  architecture
• 802.16 Protocol is concerned with the lowest two
  layers

Top Level
Bottom Level
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Protocol Architecture

• Physical Layer
• Medium
• Frequency Bands
• Transmission Layer
• Encoding/Decoding
• Preamble
• Bit Tx and Rx

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MAC and Convergence Layers

• MAC Layer
• Able to allocate channel capacity
• Convergence Layer
• Encapsulation
• Satisfy required service demands
• Services and QoS Requirements (Circuit Based,
  Variable, Fixed-Length Cells)

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IEEE 802.16 Options
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Solution WiMax

• WiMAX Forum
• Industry leaders
• WiMax is a certification mark for products that
  pass conformity and interoperability tests
• WiMax products can form wireless connections
  between them

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WiMax Network Contention

• WIFI MAC uses CSMA/CA
• All subscriber stations are competing for AP
  attention on a random basis
• Distant nodes can be repeatedly interrupted by
  closer nodes reducing their TP

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WiMax Network Contention

• WiMAX MAC uses a scheduling scheme
• A subscriber competes for initial entry
• Subscriber is allocated a time slot
• Enlarge slots
• Constrict
• Stable under overload and over subscription
• More Bandwidth efficient
• 
  

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OFDM Definition

• OFDM Orthogonal FDM
• Carrier centers are put on orthogonal frequencies
• ORTHOGONALITY - The peak of each signal coincides
  with trough of other signals
• Sub-carriers are spaced by 1/Ts

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Adaptive Modulation

• Allows system to choose highest order modulation
  pending channel conditions.
• Allows system to overcome time-selective fading.
• Increases the range that a higher modulation
  scheme can be used over.

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Adaptive Modulation
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Why OFDM?

• Resistant against multi-path using guard interval
  and cyclic prefix
• High spectrum efficiency
• Ease of filtering out noise

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Why OFDM?

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What makes OFDM different?

• Multi-path interference
• Overcomes the near-far problem

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WiMax Deployment Models

• Fixed
• Portable

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Fixed Model

• The IEEE 802.16-2004 standard is designed for
  fixed-access usage models.
• It uses a mounted antenna at the subscribers
  site.
• Fixed model is an alternative to
• cable modem,
• DSL,
• Transmit/exchange circuit (Tx/Ex), and
• Optical carrier level circuit (OC-x).

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Portable Model

• The IEEE 802.16e standard targets the mobile
  market by adding portability.
• Provides the ability for mobile clients with IEEE
  802.16e adapters to connect directly to the WiMAX
  network.
• The 802.16e standard uses Orthogonal Frequency
  Division Multiple Access (OFDMA)

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Portable Model (Continued)

• The IEEE 802.16-e standard improves last-mile
  delivery in several key aspects like
• Multi-path interference,
• delay spread, and
• robustness.

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Fixed Model
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Initial Bands of Focus

• License-Exempt 5 GHz (5.25 GHz to 5.85 GHz)
• Licensed 2.5 GHz (2.5 GHz to 2.7 GHz)
• Licensed 3.5 GHz (3.4 GHz to 3.6 GHz)

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Worldwide allocation of bands
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New Bands of Interest in Lower Frequencies

• Bands in the sub 1 GHz frequency range are being
  considered.
• The lower the frequency band, fewer the base
  stations required.

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Base Station Shipment by Frequency
Source VIOCORP
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Type of Channels

• Two forms of wireless Channels
• Non line of sight
• Lower Frequency range 2GHz to 11
• Line of sight
• Higher Frequencies ranging up to 66GHz

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NLOS and LOS

• Non-line-of-sight
• A small antenna on computer connects to a tower.
  Lower wavelength transmissions are not as easily
  disrupted by physical obstructions. They are
  better able to diffract, or bend around
  obstacles.
• Line-of-sight
• Fixed dish antenna points straight at WiMax tower
  from a rooftop or pole. Service is stronger and
  more stable, capable to send a lot of data with
  fewer errors. At higher frequencies, less
  interference and more bandwidth

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Antenna Technology

• Essential to provide high spectral efficiency,
  capacity, system performance, and reliability.
• Beam Forming
• Transmit Diversity and MIMO techniques

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Connections and Solutions

• Last Mile Broadband Access Solution
• Backhaul networks for cellular base stations
• Backhaul enterprise connections to Internet for
  WiFi hotspots
• Variety of new business services by wireless
  Internet service Provider

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Security Features

• Traffic Encrypted with Counter Mode w/ Cipher
  Block Chaining Message Authentication Code
  Protocol (CCMP)
• User Authentication using Extensible
  Authentication Protocol (EAP)
• Data Encryption using Data Encryption Standard
  (DES) or Advanced Encryption Standard (AES)

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Quality of Service

• Can be guaranteed in fixed networks
• Mac layer based on combination of Time-Division
  Multiplex (TDMA) and Frequency-Division-Duplex
• Physical layer (radio-interface-layer) adaptable
  for different QoS needs

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WiMax Growth

• Past
• Present
• Future
• Hype Cycle

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WiMax Past, Present and Future

• The WiMax Forum has estimated CPE customer
  premises equipment) availability and cost by the
  following types.
• First Generation. Fixed outdoor antenna/radio
  (similar to DBS), 2005,350
• Second Generation. Indoor directional
  antenna/radio, late 2005/2006,250
• Third Generation. Integrated system in
  laptops, 2006/2007 100

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WiMax Future

• In-Stat/MDR forecasts the BWA market will
  increase from 558.7 million last year to 1.2
  billion by the end of 2007.
• Survey of 400 wireless ISPs worldwide reveals
  that more than half of the them intend to deploy
  to WiMax equipment to lower overall equipment
  costs.

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WiMax Future
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Hype Cycle

• Hype cycle is a graphical representation of the
  maturity, adoption, and business application of
  specific technologies.
• Five Phases
• Technology Trigger
• Peak of Inflated Expectations
• Trough of Disillusionment
• Slope of Enlightenment
• Plateau of Productivity

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June 2004 Hype Cycle
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July 2005 Hype Cycle
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How Do We Get There?

• WiMax Forum and IEEE are driving the industry
  through relationships with many companies.
• Recently announced relationships with numerous
  OEMs and Carriers in support of WiMax forums
  vision.
• Various companies to implement 802.16d
  cost-effective, integrated silicon in second-half
  06.

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References

• Wikipedia.org
• TechWeb Business Technology Network
• Office Communications Presentation by Ben Willis
  http//www.ofcom.org.uk/media/speeches/2005/07/wat
  .pdf
• WiMax Forum Telephony Article
• http//www.wimaxforum.org/news/press_releases/Tel
  ephony_WiMAX.pdf
• Computer Networks by Douglas Comer
• Wireless Communications and Networks by William
  Stallings
• Intel
• http//www.intel.com/netcomms/technologies/wimax
• Breaking News, Hype Article
• http//breakingnewsblog.com/wimax/archives/wimax_
  research_report
• WiMax
• http//www.wimax.com
• Last Semesters WiMax Presentation

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Questions
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Extra Slide 1 for Connectivity

• Channel Size 1.5 20 MHz
• Flexibility allows to adapt to available spectrum
  and channel widths in different countries or
  licensed to different service providers.

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Extra Slide 2 for Connectivity

• Offers network the flexibility to support variety
  of transmitting rates such as T1 (1.5 Mbps) and
  higher data transmitting rates up to 75 Mbps on a
  single channel which supports thousands of users.

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Extra Slide 1 for Interoperability

• Point-to-multipoint broadband wireless access
  standard for systems in the frequency ranges 10
  66GHz and sub 11GHz
• Supports a variety of more efficient polling
  mechanisms that venders and carriers can choose
  to use to create IEEE 802.16 based products

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Extra Slide 2 for Interoperability

• Provides rich source of service possibilities to
  voice and data network service providers
  (supports ATM, IPv4,IPv6, Ethernet, and VLAN
  services)

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Additional Wimax Benefits

• Robust Security Features
• Good Quality Of Service (QoS)
• Support of various advanced antenna techniques
• Can be used on a variety of wireless broadband
  connections and solutions

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Scheduling Scheme

• Subscribers, even ones very close to AP, must
  wait their turn. The adaptive time slot
  assignment scheme reduces wasted bandwidth, and
  increases network efficiency
• Algorithm allows base station to balance the
  subscriber load based on the service required.
  This is how WiMax Can ensure meeting the QoS
  demands of such services as ATM.

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Additional Definition Slides

• IEEE 802.16 Air Interface Standard for fixed
  broadband wireless access systems
• Employs point-to-multipoint architecture
• Broadband MAN, in the same category as ADSL and
  Cable, but wireless

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Where does WiMax fit?

• WAN
• 802.20
• Emerging technologies/Emerging Standards
• No Current Market
• Circa 5 years

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Where does WiMax fit?

• MAN
• 802.16
• Immature Technology/Proprietary Solutions
• Emerging Market
• Mature in 18-24 months

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Where does WiMax fit?

• LAN
• 802.11
• Mature Technology/Standards Solutions
• Maturing Market

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Where does WiMax fit?

• PAN
• 802.15
• Bluetooth, Zigbee, UWB
• Mature Technology/Standards Solutions
• Immature Market

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Where does is fit?

• Bluetooth
• WPAN technology from the Bluetooth Special
  Interest Group Ericsson, IBM, Intel, Nokia and
  Toshiba
• standard for short-range transmission of digital
  voice and data
• Point-to-point and multipoint applications
• 720 Kbps data transfer within a range of 10
  meters
• Bluetooth uses omni directional radio waves that
  can transmit through walls unlicensed 2.4GHz band

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Where does is fit?

• WIFI
• Wireless Fidelity A logo from the WIFI Alliance
  
• Certifies that Ethernet devices comply with the
  IEEE 802.11
• extends 802.3 (wired Ethernet)
• Introduced in 1997

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Revisions

• Evolution of 802.16
• Originally was for bands above 10 GHZ
• Corporate access, and back haul only, but no mass
  market
• 802.16a revision was added for bands below 10 GHZ
  and NLOS
• The current revision is 802.16 2004 which
  combines prior revisions into one
• 802.16e is currently under development, it will
  extend the standard to cover mobile applications

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WiMax- Past and Present
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WiMax Hype Cycle (Details)
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Protocol Details

• Services Required
• Circuit Based
• Telephony
• Variable Length
• TCP/IP or MPEG
• Fixed Length Cell
• ATM

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Protocol Details

• MAC Layer
• Assemble data into frames
• Address Recognition
• Error Detection
• Has many formats based on the service required by
  the subscriber. Does not know what type of
  service is required

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Protocol Details

• Convergence Layer
• Understands the service required by subscriber
• It adds/removes the logic link control header,
  which prepares the proper format MAC header
  format