Positioning of GSM Mobile phones and location based Services

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Positioning of GSM Mobile phones and location
based Services
Robert Stjärnström David Haupt Peter Ferngren
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GSM basics and Positioning

• The Cell approach
• 125 35000 meter radius

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Directed antennas

• Most base stations in built up areas have
  directed antennas
• A base station often has antennas with
  60 or 120 degrees

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Timing advance

• GSM devices has timeslots
• Compensate for the distance to the base station
• 550 meter interval

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Ericsson MPS

• Ericsson Mobile Positioning System Current
  version v3.0 Supports TA (Timing
  advance) Privacy control
• MPC Mobile Positioning Center Runs on Sun
  hardware Optional SSL
• MPP Mobile Positioning Protocol Propietary
  Ericsson protocol HTTP and XML based WGS84 or
  RT90 coordinates

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MPS SDK
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Images
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Images
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Images
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Future

• MPS v4.0 UL-TOA Uplink time of
  arrival Requires new hardware and software in
  basestation 40 metre accuracy
• GPS assisted positioning Mobile devices with
  built in GPS receivers

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Location based Services

• Increased Competition for Operators Lower
  margins on traditional mobile services
• New Content and Services
• Positioning Services one area of special
  content
• Interaction with GIS i.e. Map databases

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Some Location based Services in use Today

• Tele 2 Mobil Position November 1999 Web
  interface to locate phones
• Telia Gula Sidorna Find nearest ATM, restaurant
  etc. SMS/WAP interface Routing
• Telia Botfighters Game Shoot other players
  when they are in close proximity SMS/Web
  interface

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Sources

• Mobile positioning system, master thesis by Klas
  Karlsson
• Mobile Positioning Protocol v3.0 Ericsson
• http//www.ericsson.com/mps/
• http//www.cellpoint.se
• Http//www.itsalive.com

Questions?