2.1.3 UNGUIDED MEDIA
2.1.3.1 Microwave link
A microwave link is a communications system that uses a beam
of radio waves in the microwave frequency range to transmit information between
two fixed locations on the Earth. They are crucial to many forms of
communication and impact a broad range of industries. Broadcasters use
microwave links to send programs from the studio to the transmitter location
which might be miles away, microwave links carry cellular telephone calls
between cell sites and Wireless Internet service providers use microwave links
to provide to their clients with high-speed Internet access without the need
for cable connections and Telephone companies transmit calls between switching
centers over microwave links, Although fairly recently they have been largely
supplanted by fiber optic cables
2.1.3.2 Satellite
In communications, satellite is a specialized wireless
receiver and transmitter that is launched by a rocket and placed in orbit
around the earth they are used for such diverse purposes as weather
forecasting, television broadcast, amateur radio communications, Internet
communications, and the Global Positioning System, (GPS).
After having given a general idea on the various media of
transmission, we will approach in the following the processes of optical fiber
for the routing with very great range of significant flows of information
integrated on the same line of transmission.
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