WIFI AND WIMAX

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WI-FI AND WIMAX
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What is Wi-Fi

• Wi-Fi or Wireless Fidelity is a trademark of the
  Wi-Fi Alliance for certified products
• based on the IEEE 802.11 standards.
• The term Wi-Fi is often used by the public as a
  synonym for wireless LAN (WLAN)
• Wi-Fi is supported by most personal computer
  operating systems, many game consoles, laptops,
  smartphones, printers, and other peripherals.

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What is Wimax

• WiMAX, Worldwide Interoperability for Microwave
  Access
• is a telecommunications technology that provides
  wireless transmission of data
• uses a variety of transmission modes, from
  point-to-multipoint links to portable and fully
  mobile internet access.
• The technology provides up to 3 Mbit/s broadband
  speed without the need for cables.
• The technology is based on the IEEE 802.16
  standard
• also called Broadband Wireless Access

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Wi-Fi system details

• Wi-Fi uses both single carrier direct-sequence
  spread spectrum radio technology and
  multi-carrier OFDM (Orthogonal Frequency Division
  Multiplexing) radio technology
• The regulations for unlicensed spread spectrum
  enabled the development of Wi-Fi
• Unlicensed spread spectrum was first made
  available in the US by the Federal Communications
  Commission in 1985

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Wi-Fi system advantages

• Wi-Fi allows low-cost local area networks (LANs)
  to be deployed without wires for client devices
• The price of chipsets for Wi-Fi continues to drop
• Wi-Fi has become widespread in corporate
  infrastructures.
• Unlike mobile telephones, any standard Wi-Fi
  device will work anywhere in the world.
• Wi-Fi is widely available in more than 220,000
  public hotspots and tens of millions of homes and
  corporate and university campuses worldwide

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Wi-Fi system challenges

• Spectrum assignments and operational limitations
  are not consistent worldwide
• Wi-Fi networks have limited range. A typical
  Wi-Fi home router using 802.11b or 802.11g has a
  range of 32 m (120 ft) indoors and 95 m (300 ft)
  outdoors.
• High power consumption of Wi-Fi makes lower
  battery life mobile devices.

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Wi-Fi system devices

• A wireless access point (WAP) connects a group of
  wireless devices to an adjacent wired LAN.
• Wireless adapters allow devices to connect to a
  wireless network, such as PCI, miniPCI, USB,
  ExpressCard, PC card.
• A wireless router allows wired and wireless
  Ethernet LAN devices to connect to a (usually)
  single WAN device such as cable modem or DSL
  modem
• Wireless network bridges connect a wired network
  to a wireless network such as between two
  separate homes.

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OSBRiDGE 3GN - 802.11n Access Point and UMTS/GSM
Gateway
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USB wireless adapter
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Embedded serial-to-Wi-Fi module
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City Wide Wi-Fi

• Many cities around the world announced plans for
  a city wide Wi-Fi network
• most of these projects were either canceled or
  placed on indefinite hold.
• A few were successful, for example in 2005,
  Sunnyvale, California became the first city in
  the United States to offer city wide free Wi-Fi

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Wi-Fi system uses

• A Wi-Fi enabled device such as a PC, game
  console, mobile phone, MP3 player or PDA can
  connect to the Internet
• Wi-Fi can make access publicly available at Wi-Fi
  hotspots provided either free of charge or to
  subscribers to various providers.
• There are already more than 300 metropolitan-wide
  Wi-Fi projects in progress
• Wi-Fi enables wireless voice-applications (VoWLAN
  or WVOIP).

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Wi-Fi channel congestion

• Usage of the ISM band in the 2.45 GHz range is
  also common to Bluetooth, ZigBee
• Problem in high-density areas, such as large
  apartment complexes or office buildings with many
  Wi-Fi access points
• Additionally, other devices such as microwave
  ovens, security cameras, Bluetooth devices
  cordless phones and baby monitors can interfere
• Solution is to is migrate to a Wi-Fi 5 GHz
  product, (802.11a, or the newer 802.11n if it has
  5 GHz support)

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Wi-Fi Alliance

• The Alliance aims to improving the
  interoperability of wireless local area network
  products based on the IEEE 802.11 standards.
• The Wi-Fi Alliance is a consortium of separate
  and independent companies
• The Alliance have a set of common interoperable
  products based on the family of IEEE 802.11
  standards
• The Wi-Fi Alliance certifies products via a set
  of defined test-procedures

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WiMAX Applications

• Connecting Wi-Fi hotspots to the Internet.
• Providing a wireless alternative to cable and DSL
  for broadband access.
• Providing data and telecommunications services.
• Providing a source of Internet connectivity as
  part of a business continuity plan.
• Providing portable connectivity.

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WiMAX Technical details

• WiMAX is a term coined to describe standard,
  interoperable implementations of IEEE 802.16
  wireless networks
• Wi-Fi is used for interoperable implementations
  of the IEEE 802.11 Wireless LAN standard.
• However, WiMAX is very different from Wi-Fi in
  the way it works.

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WiMAX Physical layer

• The original WiMAX is based 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
• More advanced versions, including 802.16e, also
  bring Multiple Antenna Support through MIMO
  (Multiple input-Multiple output)

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WiMAX MIMO board
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WiMAX integration with IP

• The WiMAX Forum has proposed a WiMAX network can
  be connected with an IP based core network
• Typically chosen by operators that serve as
  Internet Service Providers (ISP)
• Nevertheless the WiMAX BS provide seamless
  integration capabilities with other types of
  architectures as with packet switched Mobile
  Networks.

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WiMAX frequency allocation

• WiMAX could function on any frequency below
  66 GHz
• WiMAX Forum has published three licensed spectrum
  profiles 2.3 GHz, 2.5 GHz and 3.5 GHz
• In the USA it is 2.5 GHz primarily to Sprint
  Nextel and Clearwire.
• Some countries in Asia like India and Indonesia
  will use a mix of 2.5 GHz, 3.3 GHz and other
  frequencies
• Pakistan's Wateen Telecom uses 3.5 GHz.

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WiMAX Silicon design

• A critical requirement for the success of a new
  technology is the availability of low-cost
  chipsets and silicon implementations.
• Intel Corporation is a leader in promoting WiMAX,
  and has developed its own chipset.
• Texas Instruments, DesignArt, and picoChip are
  focused on WiMAX chip sets for base stations.
• Kaben Wireless Silicon is a provider of RF
  front-end and semiconductor IP for WiMAX
  applications.

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WiMAX Compared with Wi-Fi

• WiMAX uses 802.16 standards provide different
  types of access, from portable (similar to a
  cordless phone) to fixed (an alternative to wired
  access, where the end user's wireless termination
  point is fixed in location.)
• Wi-Fi uses unlicensed spectrum to provide access
  to a network.
• WiMAX and Wi-Fi have quite different Quality of
  Service (QoS) mechanisms.