There are two types of radio network currently in use around the world: the one-to-many (simplex communication) broadcast network commonly used for public information and mass-media entertainment, and the two-way radio (duplex communication) type used more commonly for public safety and public services such as police, fire, taxicabs, and delivery services. Cell phones are able to send and receive simultaneously by using two different frequencies at the same time. Many of the same components and much of the same basic technology applies to all three.
Simplex communication is a communication channel that sends information in one direction only.
A terrestrial network is a group of radio stations, television stations, or other electronic media outlets, that form an agreement to air, or broadcast, content from a centralized source. For example, PBS (U.S.) and BBC (U.K.) are TV networks that provide programming for local terrestrial television station affiliates to air using signals that can be picked up by the home television sets of local viewers. Large networks are mostly national, but there is also a Global Television Network.
Mass media refers to a diverse array of media technologies that reach a large audience via mass communication. The technologies through which this communication takes place include a variety of outlets.
The two-way type of radio network shares many of the same technologies and components as the broadcast-type radio network but is generally set up with fixed broadcast points (transmitters) with co-located receivers and mobile receivers/transmitters or transceivers. In this way both the fixed and mobile radio units can communicate with each other over broad geographic regions ranging in size from small single cities to entire states/provinces or countries. There are many ways in which multiple fixed transmit/receive sites can be interconnected to achieve the range of coverage required by the jurisdiction or authority implementing the system: conventional wireless links in numerous frequency bands, fibre-optic links, or microwave links. In all of these cases the signals are typically backhauled to a central switch of some type where the radio message is processed and resent (repeated) to all transmitter sites where it is required to be heard.
In electronics and telecommunications a transmitter or radio transmitter is an electronic device which produces radio waves with an antenna. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating current, the antenna radiates radio waves.
A transceiver is a device comprising both a transmitter and a receiver that are combined and share common circuitry or a single housing.
In contemporary two-way radio systems a concept called trunking is commonly used to achieve better efficiency of radio spectrum use and provide very wide-ranging coverage with no switching of channels required by the mobile radio user as it roams throughout the system coverage. Trunking of two-way radio is identical to the concept used for cellular phone systems where each fixed and mobile radio is specifically identified to the system controller and its operation is switched by the controller.
In telecommunications, trunking is a method for a system to provide network access to many clients by sharing a set of lines or frequencies instead of providing them individually. This is analogous to the structure of a tree with one trunk and many branches. Examples of this include telephone systems and the two-way radios commonly used by police agencies. Trunking, in the form of link aggregation and VLAN tagging, has been applied in computer networking as well.
The broadcast type of radio network is a network system which distributes programming to multiple stations simultaneously, or slightly delayed, for the purpose of extending total coverage beyond the limits of a single broadcast signal. The resulting expanded audience for radio programming or information essentially applies the benefits of mass-production to the broadcasting enterprise. A radio network has two sales departments, one to package and sell programs to radio stations, and one to sell the audience of those programs to advertisers.
The original inventors of radio, from Guglielmo Marconi's time on, expected it to be used for one-on-one wireless communication tasks where telephones and telegraphs could not be used because of the problems involved in stringing copper wires from one point to another, such as in ship-to-shore communications. Those inventors had no expectations whatever that radio would become a major mass media entertainment and information medium earning many millions of dollars in revenues annually through radio advertising commercials or sponsorship. These latter uses were brought about after 1920 by business entrepreneurs such as David Sarnoff, who created the National Broadcasting Company (NBC), and William S. Paley, who built Columbia Broadcasting System (CBS). These broadcasting business organizations began to be called network affiliates, because they consisted of loose chains of individual stations located in various cities, all transmitting the standard overall-system supplied fare, often at synchronized agreed-upon times. Some of these radio network stations were owned and operated by the networks, while others were independent radio owned by entrepreneurs allied with the respective networks. By selling blocks of time to advertisers, the medium was able to quickly become profitable and offer its products to listeners for free, provided they invested in a radio receiver set.
Broadcasting is the distribution of audio or video content to a dispersed audience via any electronic mass communications medium, but typically one using the electromagnetic spectrum, in a one-to-many model. Broadcasting began with AM radio, which came into popular use around 1920 with the spread of vacuum tube radio transmitters and receivers. Before this, all forms of electronic communication were one-to-one, with the message intended for a single recipient. The term broadcasting evolved from its use as the agricultural method of sowing seeds in a field by casting them broadly about. It was later adopted for describing the widespread distribution of information by printed materials or by telegraph. Examples applying it to "one-to-many" radio transmissions of an individual station to multiple listeners appeared as early as 1898.
Most radio networks also produce much of their programming. Originally, radio networks owned some or all of the stations that broadcast the network's radio format programming. Presently however, there are many networks that do not own any stations and only produce and/or distribute programming. Similarly station ownership does not always indicate network affiliation. A company might own stations in several different markets and purchase programming from a variety of networks.
A radio format or programming format describes the overall content broadcast on a radio station. In countries where radio spectrum use is legally regulated, formats may have a legal status where stations are licensed to transmit only specific formats.
Radio networks rose rapidly with the growth of regular broadcasting of radio to home listeners in the 1920s. This growth took various paths in different places. In Britain the BBC was developed with public funding, in the form of a broadcast receiver license, and a broadcasting monopoly in its early decades. In contrast, in the United States various competing commercial broadcasting networks arose funded by advertising revenue. In that instance, the same corporation that owned or operated the network often manufactured and marketed the listener’s radio.
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a sovereign country located off the north-western coast of the European mainland. The United Kingdom includes the island of Great Britain, the north-eastern part of the island of Ireland, and many smaller islands. Northern Ireland is the only part of the United Kingdom that shares a land border with another sovereign state, the Republic of Ireland. Apart from this land border, the United Kingdom is surrounded by the Atlantic Ocean, with the North Sea to the east, the English Channel to the south and the Celtic Sea to the south-west, giving it the 12th-longest coastline in the world. The Irish Sea lies between Great Britain and Ireland. The United Kingdom's 242,500 square kilometres (93,600 sq mi) were home to an estimated 66.0 million inhabitants in 2017.
The British Broadcasting Corporation (BBC) is a British public service broadcaster. Its headquarters are at Broadcasting House in Westminster, London, and it is the world's oldest national broadcasting organisation and the largest broadcaster in the world by number of employees. It employs over 20,950 staff in total, 16,672 of whom are in public sector broadcasting. The total number of staff is 35,402 when part-time, flexible, and fixed-contract staff are included.
A monopoly exists when a specific person or enterprise is the only supplier of a particular commodity. This contrasts with a monopsony which relates to a single entity's control of a market to purchase a good or service, and with oligopoly which consists of a few sellers dominating a market. Monopolies are thus characterized by a lack of economic competition to produce the good or service, a lack of viable substitute goods, and the possibility of a high monopoly price well above the seller's marginal cost that leads to a high monopoly profit. The verb monopolise or monopolize refers to the process by which a company gains the ability to raise prices or exclude competitors. In economics, a monopoly is a single seller. In law, a monopoly is a business entity that has significant market power, that is, the power to charge overly high prices. Although monopolies may be big businesses, size is not a characteristic of a monopoly. A small business may still have the power to raise prices in a small industry.
Major technical challenges to be overcome when distributing programs over long distances are maintaining signal quality and managing the number of switching/relay points in the signal chain. Early on, programs were sent to remote stations (either owned or affiliated) by various methods, including leased telephone lines, pre-recorded gramophone records and audio tape. The world's first all-radio, non-wireline network was claimed to be the Rural Radio Network, a group of six upstate New York FM stations that began operation in June 1948. Terrestrial microwave relay, a technology later introduced to link stations, has been largely supplanted by coaxial cable, fiber, and satellite, which usually offer superior cost-benefit ratios.
Many early radio networks evolved into Television networks.
Almost all radio stations in New Zealand are part of a radio network, and most are network-owned.
The Media of Poland consist of several different types of communications media including television, radio, cinema, newspapers, magazines, and Internet. During the communist regime in Poland the Stalinist press doctrine dominated and controlled Polish media. The country instituted freedom of press since the fall of communism. The Polish media system's main features are the product of the country's socio-political and economic post-communist transition. These features include: the privatisation of the press sector; the transformation of the state radio and television into public broadcasting services; influx of foreign capital into the media market and European integration of audiovisual media policies. Today the media landscape is very plural but highly polarized along political and ideological divides.
Digital audio broadcasting (DAB) is a digital radio standard for broadcasting digital audio radio services, used in many countries around the world, though not North America.
Christian radio is a category of radio formats that focus on transmitting programming with a Christian message. In the United States, where it is most established, many such broadcasters play contemporary Christian music, though many programs include talk or news programming covering economic, political or religious topics.
Public broadcasting includes radio, television and other electronic media outlets whose primary mission is public service. In much of the world, funding comes from the government, especially via annual fees charged on receivers. In the United States, public broadcasters may receive some funding from both federal and state sources, but generally most financial support comes from underwriting by foundations and businesses ranging from small shops to corporations, along with audience contributions via pledge drives. The great majority are operated as private not-for-profit corporations.
Digital radio is the use of digital technology to transmit or receive across the radio spectrum. Digital transmission by radio waves includes digital broadcasting, and especially digital audio radio services.
Licensed radio broadcasting in Ireland is one element of the wider Media of Ireland, with 85% of the population listening to a licensed service on any given day.
RTÉ Radio 1 is the principal radio channel of Irish public-service broadcaster Raidió Teilifís Éireann and is the direct descendant of Dublin radio station 2RN, which began broadcasting on a regular basis on 1 January 1926. The station is a rare modern example of a mixed radio channel, offering a wide spectrum of programming which is mainly speech-based but also includes a fair amount of music.
BBC Radio Nottingham is a BBC Local Radio station serving the English county of Nottinghamshire. It broadcasts on FM, DAB radio and Freeview from studios located on London Road in Nottingham city centre.
Radio broadcasting began in New Zealand in 1922, and is now dominated by almost 30 radio networks and station groups. The Government has dominated broadcasting since 1925, but through privatisation and deregulation has allowed commercial talk and music stations to reach large audiences. New Zealand also has several radio stations serving Māori tribes, Pacific Island communities, ethnic minorities, evangelical Christians and special interests.
Kerrang! Radio is a specialist digital rock music radio station currently broadcasting to the United Kingdom on Freeview and various online platforms. It is owned and operated by Bauer Radio and forms part of Bauer's National portfolio of radio brands. The station was previously available on DAB radio, though latterly in London only, and was available on FM in the West Midlands from 2004 to 2013.
Polskie Radio Spółka Akcyjna is Poland's state-owned national public-service radio broadcasting organization.
Radio Poland is the official international broadcasting station of Poland.
Digital Audio Broadcasting in Ireland is one form of digital radio transmission in the state. It was launched to the public on 30 November 2006, with trials taking place in 1998, 2001 and 2006. Currently, 56% of Ireland's population - mainly in Counties Cork, Limerick and the North East - can receive permanent DAB services. Geographic coverage on a portable or car radio is much less. In contrast, all the RTE stations on the DAB multiplex are also available nationwide via Saorsat and about 99% geographic coverage is possible via DVB. Generic DVB receivers do need mains, but are typically cheaper than DAB radios. Many portable DAB radio sets have 1/10th to 1/50th of the running time of an AM/FM set, typically giving only 6 hours use. There are also in-dash DVB Terrestrial receivers for cars, though it's illegal for the driver to watch the TV channels.
Bauer Radio is a UK-based radio division of the Bauer Media Group.
Radio Zet – Polish commercial radio station. The current owner of the station is Eurozet. The Radio started broadcasting on 28 September 1990, being the first commercial radio station in Warsaw and the second in Poland after RMF FM in Krakow.
The radio technology known as Digital Audio Broadcasting, and its TV sibling, Digital Multimedia Broadcasting (DMB), is being operated in several regions worldwide, either in the form of full services, or as feasibility studies.
RTÉ Radio is a division of the Irish national broadcasting organisation Raidió Teilifís Éireann. RTÉ Radio broadcasts four analogue channels and five digital channels nationwide.
MediaWorks Radio is the radio division of MediaWorks New Zealand. MediaWorks operates 9 radio brands nationwide across New Zealand with the majority of the programming on these stations based from Auckland, in addition to the nationwide brands MediaWorks also operate several local radio stations in certain markets.
ZM Waikato is contemporary hit radio network in Hamilton, New Zealand. It is owned by New Zealand Media and Entertainment, and broadcasts via FM, and worldwide via the Internet. The network targets the 15–39 demographic specialises in a chart-music playlist of pop, rock, hip hop and dance music.