Concept
Broadcasting
Related concepts (51)
Pirate radio
Pirate radio or a pirate radio station is a radio station that broadcasts without a valid license. In some cases, radio stations are considered legal where the signal is transmitted, but illegal where the signals are received—especially when the signals cross a national boundary. In other cases, a broadcast may be considered "pirate" due to the nature of its content, its transmission format (especially a failure to transmit a station identification according to regulations), or the transmit power (wattage) of the station, even if the transmission is not technically illegal (such as an amateur radio transmission).
Effective radiated power
Effective radiated power (ERP), synonymous with equivalent radiated power, is an IEEE standardized definition of directional radio frequency (RF) power, such as that emitted by a radio transmitter. It is the total power in watts that would have to be radiated by a half-wave dipole antenna to give the same radiation intensity (signal strength or power flux density in watts per square meter) as the actual source antenna at a distant receiver located in the direction of the antenna's strongest beam (main lobe).
Broadcast license
A broadcast license is a type of spectrum license granting the licensee permission to use a portion of the radio frequency spectrum in a given geographical area for broadcasting purposes. The licenses generally include restrictions, which vary from band to band. Spectrum may be divided according to use. As indicated in a graph from the National Telecommunications and Information Administration (NTIA), frequency allocations may be represented by different types of services which vary in size.
In-band on-channel
In-band on-channel (IBOC) is a hybrid method of transmitting digital radio and analog radio broadcast signals simultaneously on the same frequency. The name refers to the new digital signals being broadcast in the same AM or FM band (in-band), and associated with an existing radio channel (on-channel). By utilizing additional digital subcarriers or sidebands, digital information is "multiplexed" on existing signals, thus avoiding re-allocation of the broadcast bands. IBOC relies on unused areas of the existing spectrum to send its signals.
Radio advertisement
In the United States, commercial radio stations make most of their revenue by selling airtime to be used for running radio advertisements. These advertisements are the result of a business or a service providing a valuable consideration, usually money, in exchange for the station airing their commercial or mentioning them on air. The most common advertisements are "spot commercials", which normally last for no more than one minute, and longer programs, commonly running up to one hour, known as "informercials".
Community radio
Community radio is a radio service offering a third model of radio broadcasting in addition to commercial and public broadcasting. Community stations serve geographic communities and communities of interest. They broadcast content that is popular and relevant to a local, specific audience but is often overlooked by commercial (or) mass-media broadcasters. Community radio stations are operated, owned, and influenced by the communities they serve.
Military communications
Military communications or military signals involve all aspects of communications, or conveyance of information, by armed forces. Examples from Jane's Military Communications include text, audio, facsimile, tactical ground-based communications, naval signalling, terrestrial microwave, tropospheric scatter, satellite communications systems and equipment, surveillance and signal analysis, security, direction finding and jamming. The most urgent purposes are to communicate information to commanders and orders from them.
Studio transmitter link
A studio transmitter link (or STL) sends a radio station's or television station's audio and video from the broadcast studio or origination facility to a radio transmitter, television transmitter or uplink facility in another location. This is accomplished through the use of terrestrial microwave links or by using fiber optic or other telecommunication connections to the transmitter site. This is often necessary because the best locations for an antenna are on top of a mountain, where a much shorter radio tower is required, but where locating a studio may be impractical.
Signal strength in telecommunications
In telecommunications, particularly in radio frequency engineering, signal strength refers to the transmitter power output as received by a reference antenna at a distance from the transmitting antenna. High-powered transmissions, such as those used in broadcasting, are expressed in dB-millivolts per metre (dBmV/m). For very low-power systems, such as mobile phones, signal strength is usually expressed in dB-microvolts per metre (dBμV/m) or in decibels above a reference level of one milliwatt (dBm).
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 commonly "microbroadcasting") and broadcast translators. LPAM, LPFM and LPTV are in various levels of use across the world, varying widely based on the laws and their enforcement.