Microwave

Electromagnetic radiation beyond the frequency range used for radio and television, can also be used to transport information.In particular,many long distance telephone companies use microwave transmissions to carry telephone conversations.A few large companies have also installed microwave communication systems as part of the company's network system.Although microwaves are merely a higher frequency version of radio waves,they behave differently.Instead of broadcasting in all directions,a microwave transmission can be aimed in a single direction,preventing others from intercepting the signal.In addition,microwave transmission can carry more information than lower RF frequency.However,because microwaves cannot penetrate metal structures,microwave transmission works best when a clear path exists between the transmitter and receiver.As a result,most microwave installation consists of two towers that are taller than the surrounding buildings and vegetation, each with a microwave transmitter aimed at a microwave receiver on the other.