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2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
2010fall ch19 otgonbayar
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2010fall ch19 otgonbayar

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J.EL310

J.EL310

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  • 1. Satellite Communications
    J.TC08D721 Ì.Îòãîíáàÿð
    J.TC07D031 Á.Áóðìàà
    J.TC08D708 Ò.Öýíäñ¿ðýí
  • 2. contenter
    Satellite communication
    Transponders
    Attitude Control Apparatus
    Power Supply
    Radio Relay Equipment
    Low Earth Orbiting Satellite
    Very Small Aperture Terminal
    Satellite application issues
  • 3. 1998 LEO Iridium
    2002 MEO Teledesic
    1962 GEO Telstar
    Satellite communication
  • 4. SATELLITE TECHNOLOGY
  • 5. 1. domestic
    2. regional
    3. international
    Satellite fall into:
  • 6.
  • 7. The receiving station can be mobile, which offers coverage from a single
    satellite.
    Within the coverage range of a single satellite, circuit cost is independent
    of distance.
    Large amounts of bandwidth are available over satellite circuits, making voice, video, and high-speed data circuits available.
    Advantages
  • 8.
    • A transponder is a radio relay station on board the satellite.
  • Transponders
    The downlinksignal is applied to a high-power amplifier, using a traveling wave tube orsolid-state amplifier as the output device.
    Echostar 9 (also known as Telstar 13 and Intelsat
    Americas 13), which was launched in August 2003, has 2 Ka-, 32 Ku-, and 24 C-bandtransponders.
  • 9. A spin-stabilized satellite rotates on its axis at about 100 rpm.
    three-axis stabilization, which
    consists of a gyroscopic stabilizer inside the vehicle.
    Attitude Control Apparatus
  • 10. Satellites are powered by solar batteries. Power is conserved by turning offunused equipment with signals from the Earth.
    Solar cell life is a major factor that limits the workinglife of a satellite.
    Power Supply
  • 11. Radio Relay Equipment
  • 12. Iridium launched commercial voice, fax, paging, and narrow-band data service in
    2001, using a network of 66 operational satellites plus six in-orbit backups.
    Satellites are connected via intersatellite links to the four nearest neighbors
    and to an Earth station.
    Low Earth Orbiting Satellite
  • 13. Very Small Aperture Terminal
  • 14. The hubs control demand assignment to the satellite and monitor and diagnose
    network performance.
    Demand is allocated in one of the four ways
    -pure aloha
    -slotted aloha
    -TDMA and spread spectrum.
    The first three methods generally are used
    on Ku-band and the last on C-band.
    VSAT provides bandwidth as high as T1/E1 and as low as the customer needs to go.
  • 15. The remote station has an antenna and a receiving unit, which is about the
    size of a personal computer base unit.
    The primary application for VSAT is data, although it can also carry voice
    and video.
    Typically, C-band VSATs carry 9.6 Kbps data, and Ku-band VSATs carry 56 or 64 Kbps data; some systems carry a full or fractional T1/E1.
    The primary advantage of VSAT is its ability
    to support multiple locations.
  • 16. In one sense, satellite applications diminish as terrestrial and undersea fiber-optic
    circuits become more plentiful and economical, but satellite services are still
    uniquely suited for many applications.
    SATELLITE APPLICATION ISSUES
  • 17. Thank you for
    your attention

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