Satellite
- specialised wireless receiver n transmitter.- launched by rocket, placed in orbit ard the earth
- has dish-like-aerial at ground station.
- aerial used 4 sending n receiving signals.
Geostationary satellites
- revolve arf earth, appear to be stationary. revolve at the same speed as the earth's spin.- orbit the earth abt 35000km above the equator.
- can 'see' approximately 40 per cent of earth's surface. 3 for worldwide coverage.
Use of sat
- scientific sat - observation such as astronomical observetions.- weather sat - useful tools used to monitor weather n climate of earth. useful providing storm warning, flood n forest fire prediction.
- navigation sat - used in cars, ships n aircraft to help in navigation, tracking devices in wildlife management.
- military sat - provideprotection to country by defecting intruders. often used 4 gathering intelligence.
- remote sensing n geophysisc sat - sensing imminent disasters, crops growing, spillage of oil or chemicals, direct fishermen 4 fishing spot.
Advantages of sat communication.
- Unlimited coverage- Effective
- Less costly to set up, maintain & operate
- More reliable
- Multicasting
- Ability to support wide range of device n app
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