Microbroadcasting is the process of
broadcasting
Broadcasting is the data distribution, distribution of sound, audio audiovisual content to dispersed audiences via a electronic medium (communication), mass communications medium, typically one using the electromagnetic spectrum (radio waves), ...
a message to a relatively small audience. This is not to be confused with
low-power broadcasting
Low-power broadcasting is broadcasting by a broadcast station at a low transmitter power output to a smaller service area than "full power" stations within the same region. It is often distinguished from "micropower broadcasting" (more common ...
.
Microbroadcasting, in radio terms, is the use of low-power transmitters (often
Title 47 CFR Part 15
Code of Federal Regulations, 'Title 47, Part 15(47 CFR 15) is an oft-quoted part of Federal Communications Commission (FCC) rules and regulations regarding unlicensed transmissions. It is a part of Title 47 of the Code of Federal Regulatio ...
in the United States, or its equivalent elsewhere) to broadcast a radio signal over the space of a neighborhood or small town.
Similar to
pirate radio
Pirate radio is a radio station that broadcasts without a valid license, whether an invalid license or no license at all. In some cases, radio stations are considered legal where the signal is transmitted, but illegal where the signals are rec ...
broadcasting, microbroadcasters generally operate without a license from the local regulation body, but sacrifice range in favor of using legal power limits (for example, 100 mW for
medium wave
Medium wave (MW) is a part of the medium frequency (MF) radio band used mainly for AM radio broadcasting. The spectrum provides about 120 channels with more limited sound quality than FM stations on the FM broadcast band. During the daytim ...
broadcasts in the United States). Higher power levels can be achieved using
carrier current
Carrier current transmission, originally called wired wireless, employs guided low-power Radio frequency, radio-frequency signals, which are transmitted along electrical conductors. The transmissions are picked up by receivers that are either conne ...
techniques, which are widely used in colleges and universities. Both
AM and
FM bands are used, although AM tends to have better propagation characteristics at low power.
Microbroadcasting is also used by schools and businesses to serve just the immediate campus of the operation; well-known uses include
audio tour
An audio tour or audio guide provides a Sound recording, recorded spoken commentary, normally through a handheld device, to a visitor attraction such as a museum. They are also available for self-guided tours of outdoor locations, or as a part of ...
guide systems, airport information services, and
drive-in theater
A drive-in theater/theatre or drive-in cinema is a form of movie theater, cinema structure consisting of a large outdoor movie screen, a projection booth, a concession stand, and a large parking area for automobiles. Within this enclosed area, c ...
s, which often provide movie audio over the driver's car audio system. It has also been adopted as an advertising technique, particularly by car dealers and real estate agents.
References
External links
Toward Polymorphous Radioby Tetsuo Kogawa—article about the Mini-FM movement (microbroadcasting in Japan) in the 1980s.
Broadcasting
Community radio
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