Wireless Telecommunications

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Wireless Telecommunications

• Presented by
• Susanne Cochez
• Nicole Clark
• Wade Brett
• Rojae Charity

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Introduction

• History
• Major Manufacturers
• Cell Systems
• Cell Access Technologies
• Cells in the Future
• Problems with Cell Phones

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History

• 1947 - Researchers looked at crude mobile (car)
  phones and realized they could increase the
  traffic capacity of mobile phones substantially.
• 1948 - ATT  proposed that the FCC allocate a
  large number of radio-spectrum frequencies
• 1968 - FCC increased the frequencies allocation,
  freeing the airwaves for more mobile phones
• 1977 - ATT and Bell Labs had constructed a
  prototype cellular system

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• 1979 - In a separate venture, the first
  commercial cellular telephone system began
  operation in Tokyo.
• 1981 - Motorola and American Radio telephone
  started a second U.S. cellular radio-telephone
  system.
• 1983 - The first American commercial analog
  cellular service or AMPS (Advanced Mobile Phone
  Service) was made available in Chicago by
  Ameritech.
• 1987 - Cellular telephone subscribers exceeded
  one million and the airways were crowded.

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Major Manufacturers

• Nokia
• Motorola
• Audiovox
• Ericksson

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Cell Systems

• Digital cell phones use the same radio technology
  as analog phones, but they use it in a different
  way.
• Analog systems do not fully utilize the signal
  between the phone and the cellular network --
  analog signals cannot be compressed and
  manipulated as easily as a true digital signal.

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Cellular Access Technologies

• Frequency division multiple access (FDMA)
• Time division multiple access (TDMA)
• Code division multiple access (CDMA)

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FDMA

• FDMA puts each call on a separate frequency

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TDMA

• TDMA assigns each call a certain portion of time
  on a designated frequency

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CDMA

• CDMA gives a unique code to each call and spreads
  it over the available frequencies.

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Cells in the Future

• Third-generation wireless phones may look more
  like hand held computers, with features such as
  video-conferencing, advanced personal calendar
  functions and multi-player gaming.
• Another futuristic feature, will include making
  every day purchases through cellular
  communication with computer operated systems.

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Problems with Cell Phones

• Cloning
• Hazardous while driving
• Radiation causing cancer

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Questions?