Microbroadcasting
Encyclopedia
Microbroadcasting is the process of broadcasting a message to a relatively small audience. This is not to be confused with low-power broadcasting
.
Microbroadcasting, in radio terms, is the use of low-power transmitters (often Part 15 in the United States, or its equivalent elsewhere) to broadcast a radio signal over the space of a neighborhood or small town. Similarly to pirate radio
, 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 broadcasts in the United States). Higher power levels can be achieved using carrier current
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
guide systems, airport information services, and drive-in theater
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.
Low-power broadcasting
Low-power broadcasting is electronic broadcasting at very low power and low cost, to a small community area.The terms "low-power broadcasting" and "micropower broadcasting" should not be used interchangeably, because the markets are not the same...
.
Microbroadcasting, in radio terms, is the use of low-power transmitters (often Part 15 in the United States, or its equivalent elsewhere) to broadcast a radio signal over the space of a neighborhood or small town. Similarly to pirate radio
Pirate radio
Pirate radio is illegal or unregulated radio transmission. The term is most commonly used to describe illegal broadcasting for entertainment or political purposes, but is also sometimes used for illegal two-way radio operation...
, 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 broadcasts in the United States). Higher power levels can be achieved using carrier current
Carrier current
Carrier current is a method of low power AM radio transmission that uses the AC electrical system of a building to propagate a medium frequency, AM signal to a relatively small area, such as a building or a group of buildings...
techniques, which are widely used in colleges and universities. Both AM
AM broadcasting
AM broadcasting is the process of radio broadcasting using amplitude modulation. AM was the first method of impressing sound on a radio signal and is still widely used today. Commercial and public AM broadcasting is carried out in the medium wave band world wide, and on long wave and short wave...
and FM
FM broadcasting
FM broadcasting is a broadcasting technology pioneered by Edwin Howard Armstrong which uses frequency modulation to provide high-fidelity sound over broadcast radio. The term "FM band" describes the "frequency band in which FM is used for broadcasting"...
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
Audio tour
An audio tour or audio guide provides a 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 an organised tour. It provides background, context, and information...
guide systems, airport information services, and drive-in theater
Drive-in theater
A drive-in theater is a form of cinema structure consisting of a large outdoor screen, a projection booth, a concession stand and a large parking area for automobiles. Within this enclosed area, customers can view movies from the privacy and comfort of their cars.The screen can be as simple as a...
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.
External links
- Toward Polymorphous Radio by Tetsuo Kogawa — article about the Mini-FM movement (microbroadcasting in Japan) in the 1980s