See Also: Microwave Communications
Microwave (see Microwave(s) ) Radio is used for short - and/or long-haul communications. The radio system sends
signals from tower to tower, using Frequencys typically between 890 megaHertz (Hz) and 20 gigahertz. Microwave communications first came into widespread use to
connect Television broadcast stations with network studios and to connect parts of the
nationwide long-distance Telephone network. Both applications demanded extremely high reliability. Between a
network headquarters on the East Coast and a television broadcast station in the
midwest there may be 30 or 40 microwave Repeaters. If any of the microwave repeaters fail, the network feed can be lost by
the local television station. The rarity of such failures is evidence of
microwave communications system reliability.
Microwave frequencies are also used to communicate to and from satellites (see Satellite - Artificial). While one major advantage of microwave signals is that they do not require
cable, they also have the distinct disadvantage of only traveling in straight
lines or lines of sight. Since the towers (see Antenna) must be in sight of each other, placing the towers can be a difficult task.
Most terrestrial microwave systems have a maximum range of approximately 30
miles, at which point a repeater station is required.