Introduction to Data Communications
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Microwaves operate at high operating frequencies of 3 to 10 GHz. This allows them to carry large quantities of data due to the large bandwidth.

Advantages:

  1. They require no right of way acquisition between towers.
  2. They can carry high quantities of information due to their high operating frequencies.
  3. Low cost land purchase: each tower occupies small area.
  4. High frequency/short wavelength signals require small antenna.

Disadvantages:

  1. Attenuation by solid objects: birds, rain, snow and fog.
  2. Reflected from flat surfaces like water and metal.
  3. Diffracted (split) around solid objects
  4. Refracted by atmosphere, thus causing beam to be projected away from receiver.

16d. Satellite

Satellites are transponders that are set in a geostationary orbit directly over the equator. A transponder is a unit that receives on one frequency and retransmits on another. The geostationary orbit is 36,000 km from the Earth's surface. At this point, the gravitational pull of the Earth and the centrifugal force of Earths rotation are balanced and cancel each other out. Centrifugal force is the rotational force placed on the satellite that wants to fling it out to space.

Introduction to Data Communications
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