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In the context of broadcasting, backhaul refers to uncut program content that is transmitted point-to-point to an individual television station or radio station, broadcast network or other receiving entity where it will be integrated into a finished TV show or radio show. The term is independent of the medium being used to send the backhaul, but communications satellite transmission is very common. When the medium is satellite, it is called a wildfeed.
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.
In telecommunications, a point-to-point connection refers to a communications connection between two communication endpoints or nodes. An example is a telephone call, in which one telephone is connected with one other, and what is said by one caller can only be heard by the other. This is contrasted with a point-to-multipoint or broadcast connection, in which many nodes can receive information transmitted by one node. Other examples of point-to-point communications links are leased lines, microwave radio relay and two-way radio.
A television station is a set of equipment managed by a business, organisation or other entity, such as an amateur television (ATV) operator, that transmits video content via radio waves directly from a transmitter on the earth's surface to a receiver on earth. Most often the term refers to a station which broadcasts structured content to an audience or it refers to the organization that operates the station. A terrestrial television transmission can occur via analog television signals or, more recently, via digital television signals. Television stations are differentiated from cable television or other video providers in that their content is broadcast via terrestrial radio waves. A group of television stations with common ownership or affiliation are known as a TV network and an individual station within the network is referred to as O&O or affiliate, respectively.
Backhauls are also referred to sometimes as "clean feeds", being "clean" in the sense that they lack any of the post-production elements that are added later to the feed's content (i.e. on-screen graphics, voice-overs, bumpers, etc.) during the integration of the backhaul feed into a finished show. In live sports production, a backhaul is used to obtain live game footage (usually for later repackaging in highlights shows) when an off-air source is not readily available. In this instance the feed that is being obtained contains all elements except for TV commercials or radio ads run by the host network's master control. This is particularly useful for obtaining live coverage of post-game press conferences or extended game highlights ("melts"), since the backhaul may stay up to feed these events after the network has concluded their broadcast.
In television technology, a clean feed is a video signal that does not have added graphics and text. This video signal is used in sport production to allow different television stations to add their own digital on-screen graphic image on a common signal, or in news broadcasting to produce two or more different streams, each one with the same picture but in different languages.
Post-production is part of the process of filmmaking, video production, radio production and photography. Post-production includes all stages of production occurring after shooting or recording individual program segments.
A digital on-screen graphic is a watermark-like station logo that most television broadcasters overlay over a portion of the screen area of their programs to identify the channel. They are thus a form of permanent visual station identification, increasing brand recognition and asserting ownership of the video signal. In some cases, the graphic also shows the name of the current program. Some television networks use an on-screen graphic to advertise upcoming programs.
Electronic news gathering, including "live via satellite" interviews, reporters' live shots, and sporting events are all examples of radio or television content that is backhauled to a station or network before being made available to the public through that station or network. Cable TV channels, particularly public, educational, and government access (PEG) along with (local origination) channels, may also backhauled to cable headends before making their way to the subscriber. Finished network feeds are not considered backhauls, even if local insertion is used to modify the content prior to final transmission.
An interview is a conversation where questions are asked and answers are given. In common parlance, the word "interview" refers to a one-on-one conversation between an interviewer and an interviewee. The interviewer asks questions to which the interviewee responds, usually so information may be transferred from interviewee to interviewer. Sometimes, information can be transferred in both directions. It is a communication, unlike a speech, which produces a one-way flow of information.
Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna which radiates the waves, and received by a radio receiver connected to another antenna. Radio is very widely used in modern technology, in radio communication, radar, radio navigation, remote control, remote sensing and other applications. In radio communication, used in radio and television broadcasting, cell phones, two-way radios, wireless networking and satellite communication among numerous other uses, radio waves are used to carry information across space from a transmitter to a receiver, by modulating the radio signal in the transmitter. In radar, used to locate and track objects like aircraft, ships, spacecraft and missiles, a beam of radio waves emitted by a radar transmitter reflects off the target object, and the reflected waves reveal the object's location. In radio navigation systems such as GPS and VOR, a mobile receiver receives radio signals from navigational radio beacons whose position is known, and by precisely measuring the arrival time of the radio waves the receiver can calculate its position on Earth. In wireless radio remote control devices like drones, garage door openers, and keyless entry systems, radio signals transmitted from a controller device control the actions of a remote device.
Public, educational, and government access television refers to three different cable television narrowcasting and specialty channels. Public-access television was created in the United States between 1969 and 1971 by the Federal Communications Commission (FCC) and has since been mandated under the Cable Communications Act of 1984, which is codified under 47 USC § 531. PEG channels consist of:
There exists a dedicated group of enthusiasts who use TVRO (TV receive-only) gear such as satellite dishes to peek in on backhaul signals that are available on any of the dozens of broadcast satellites that are visible from almost any point on Earth. In its early days, their hobby was strengthened by the fact that most backhaul was analog and "in the clear" (unscrambled or unencrypted) which made for a vast smorgasbord of free television available for the technically inclined amateur. In recent years, full-time content and cable channels have added encryption and conditional access, and occasional signals are steadily becoming digital, which has had a deleterious effect on the hobby.
In cryptography, plaintext usually means unencrypted information pending input into cryptographic algorithms, usually encryption algorithms. Cleartext usually refers to data that is transmitted or stored unencrypted.
In cryptography, encryption is the process of encoding a message or information in such a way that only authorized parties can access it and those who are not authorized cannot. Encryption does not itself prevent interference, but denies the intelligible content to a would-be interceptor. In an encryption scheme, the intended information or message, referred to as plaintext, is encrypted using an encryption algorithm – a cipher – generating ciphertext that can be read only if decrypted. For technical reasons, an encryption scheme usually uses a pseudo-random encryption key generated by an algorithm. It is in principle possible to decrypt the message without possessing the key, but, for a well-designed encryption scheme, considerable computational resources and skills are required. An authorized recipient can easily decrypt the message with the key provided by the originator to recipients but not to unauthorized users.
Conditional access or conditional access system is the protection of content by requiring certain criteria to be met before granting access to the content. The term is commonly used in relation to digital television systems and to software.
Some digital signals remain freely accessible (sometimes using Ku band dishes as small as one meter) under the international DVB-S standard or the US Motorola-proprietary Digicipher system. The small dishes may either be fixed (much like DBS antennas), positioned using a rotor (usually DiSEqC-standard) or may be toroidal in design (twin toroidal reflectors focus the incoming signal as a line, not a point, so that multiple LNBs may receive signal from multiple satellites). A "blind-search" receiver is often used to try every possible combination of frequency and bitrate to search for backhaul signals on individual communication satellites.
Free-to-air (FTA) are television (TV) and radio services broadcast in clear (unencrypted) form, allowing any person with the appropriate receiving equipment to receive the signal and view or listen to the content without requiring a subscription, other ongoing cost or one-off fee. In the traditional sense, this is carried on terrestrial radio signals and received with an antenna.
The Ku band is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz). The symbol is short for "K-under", because it is the lower part of the original NATO K band, which was split into three bands because of the presence of the atmospheric water vapor resonance peak at 22.24 GHz, (1.35 cm) which made the center unusable for long range transmission. In radar applications, it ranges from 12 to 18 GHz according to the formal definition of radar frequency band nomenclature in IEEE Standard 521-2002.
Digital Video Broadcasting – Satellite (DVB-S) is the original DVB standard for Satellite Television and dates from 1995, in its first release, while development lasted from 1993 to 1997. The first commercial application was by Galaxy in Australia, enabling digitally broadcast, satellite-delivered Television to the public.
The 1992 documentary Feedwas compiled almost entirely using unedited backhaul from political campaign coverage by local and network television. A similar documentary about the 1992 U.S. presidential election named Spin was made in the same way in 1995.
A documentary film is a nonfictional motion picture intended to document reality, primarily for the purposes of instruction, education, or maintaining a historical record. "Documentary" has been described as a "filmmaking practice, a cinematic tradition, and mode of audience reception" that is continually evolving and is without clear boundaries. Documentary films were originally called 'actuality' films and were only a minute or less in length. Over time documentaries have evolved to be longer in length and to include more categories, such as educational, observational, and even 'docufiction'. Documentaries are also educational and often used in schools to teach various principles. Social media platforms such as YouTube, have allowed documentary films to improve the ways the films are distributed and able to educate and broaden the reach of people who receive the information.
A political campaign is an organized effort which seeks to influence the decision making progress within a specific group. In democracies, political campaigns often refer to electoral campaigns, by which representatives are chosen or referendums are decided. In modern politics, the most high-profile political campaigns are focused on general elections and candidates for head of state or head of government, often a president or prime minister.
Spin is a 1995 documentary film by Brian Springer composed of raw satellite feeds featuring politicians' pre-appearance planning. It covers, not only the presidential election, but also the 1992 Los Angeles riots as well as the Operation Rescue abortion protests.
Cable television is a system of delivering television programming to consumers via radio frequency (RF) signals transmitted through coaxial cables, or in more recent systems, light pulses through fiber-optic cables. This contrasts with broadcast television, in which the television signal is transmitted over the air by radio waves and received by a television antenna attached to the television; or satellite television, in which the television signal is transmitted by a communications satellite orbiting the Earth and received by a satellite dish on the roof. FM radio programming, high-speed Internet, telephone services, and similar non-television services may also be provided through these cables. Analog television was standard in the 20th century, but since the 2000s, cable systems have been upgraded to digital cable operation. James VanDamager invented CATV in 1948 in Milpitas, California.
A television network is a telecommunications network for distribution of television program content, whereby a central operation provides programming to many television stations or pay television providers. Until the mid-1980s, television programming in most countries of the world was dominated by a small number of terrestrial networks. Many early television networks evolved from earlier radio networks.
Television receive-only (TVRO) is a term used chiefly in North America to refer to the reception of satellite television from FSS-type satellites, generally on C-band analog; free-to-air and unconnected to a commercial DBS provider. TVRO was the main means of consumer satellite reception in the United States and Canada until the mid-1990s with the arrival of direct-broadcast satellite television services such as PrimeStar, USSB, Bell TV, DirecTV, Dish Network, Sky TV that transmit Ku signals. While these services are at least theoretically based on open standards, the majority of services are encrypted and require proprietary decoder hardware. TVRO systems relied on feeds being transmitted unencrypted and using open standards, which heavily contrasts to DBS systems in the region.
Terrestrial television is a type of television broadcasting in which the television signal is transmitted by radio waves from the terrestrial (Earth-based) transmitter of a television station to a TV receiver having an antenna. The term terrestrial is more common in Europe and Latin America, while in the United States it is called broadcast or over-the-air television (OTA). The term "terrestrial" is used to distinguish this type from the newer technologies of satellite television, in which the television signal is transmitted to the receiver from an overhead satellite, cable television, in which the signal is carried to the receiver through a cable, and Internet Protocol television, in which the signal is received over an Internet stream or on a network utilizing the Internet Protocol. Terrestrial television stations broadcast on television channels with frequencies between about 52 and 600 MHz in the VHF and UHF bands. Since radio waves in these bands travel by line of sight, reception is limited by the visual horizon to distances of 40–60 miles (64–97 km).
Television is one of the major mass media of the United States. As of 2011, household ownership of television sets in the country is 96.7%, with approximately 114,200,000 American households owning at least one television set as of August 2013. The majority of households have more than one set. The peak ownership percentage of households with at least one television set occurred during the 1996–97 season, with 98.4% ownership.
A diplexer is a passive device that implements frequency-domain multiplexing. Two ports are multiplexed onto a third port. The signals on ports L and H occupy disjoint frequency bands. Consequently, the signals on L and H can coexist on port S without interfering with each other.
Malaysian television broadcasting was introduced on 28 December 1963. Colour television was introduced on 28 December 1978. Full-time colour transmissions were officially inaugurated on New Year's Day 1982. There are currently 8 national free-to-air terrestrial television stations in Malaysia and 2 national pay subscription television stations in Malaysia.
WWOR EMI Service was a New York City-based American cable television channel that operated as a superstation feed of Secaucus, New Jersey-licensed WWOR-TV. The service was uplinked to satellite from Syracuse, New York by Eastern Microwave, Inc., which later sold the satellite distribution rights to the Advance Entertainment Corporation subsidiary of Advance Publications, a Syracuse-based company that also owned various print, broadcast, and cable television properties.
The Open Student Television Network, also known as OSTN, is a USA national student television network, headquartered in downtown Cleveland, Ohio.
In broadcasting, digital subchannels are a method of transmitting more than one independent program stream simultaneously from the same digital radio or television station on the same radio frequency channel. This is done by using data compression techniques to reduce the size of each individual program stream, and multiplexing to combine them into a single signal. The practice is sometimes called "multicasting".
Satellite television is a service that delivers television programming to viewers by relaying it from a communications satellite orbiting the Earth directly to the viewer's location. The signals are received via an outdoor parabolic antenna commonly referred to as a satellite dish and a low-noise block downconverter.
In broadcasting, local insertion is the act or capability of a broadcast television station, radio station or cable system to insert or replace part of a network feed with content unique to the local station or system. Most often this is a station identification, but is also commonly used for television or radio advertisements, or a weather or traffic report. A digital on-screen graphic, commonly a translucent watermark, may also be keyed (superimposed) with a television station ID over the network feed using a character generator using genlock. In cases where individual broadcast stations carry programs separate from those shown on the main network, this is known as regional variation or an opt-out.
A free-to-air or FTA Receiver is a satellite television receiver designed to receive unencrypted broadcasts. Modern decoders are typically compliant with the MPEG-2/DVB-S and more recently the MPEG-4/DVB-S2 standard for digital television, while older FTA receivers relied on analog satellite transmissions which have declined rapidly in recent years.
The television industry in China includes high-tech program production, transmission and coverage. China Central Television is China's largest and most powerful national television station. By 1987, two-thirds of people in China had access to television, while today, over 3,000 channels are available in the country.
A television production truck is a small mobile production control room to allow filming of events and video production at locations outside a regular television studio. They are used for remote broadcasts, outside broadcasting (OB), and electronic field production (EFP). Some require a crew of as many as 30 people, with additional trucks for additional equipment as well as a satellite truck, which transmits video back to the studio by sending it up through a communications satellite using a satellite dish, which then transmits it back down to the studio. In contrast, some production trucks include a satellite transmitter and satellite dish for this purpose in a single truck body to save space, time and cost.
NASA TV is the television service of the United States government agency NASA. It is broadcast by satellite with a simulcast over the Internet. Local cable television providers across the United States and amateur television repeaters may carry NASA TV at their own discretion, as NASA-created content is considered a work of the U.S. government and is within the public domain. NASA TV is also available via various cable, satellite, and over-the-top media services around the world. The network was formally created in the early 1980s to provide NASA managers and engineers with real-time video of missions. NASA has operated a television service since the beginning of the space program for archival purposes, and in order to provide media outlets with video footage.
Television (TV) started broadcasting in Afghanistan in 1977, flourishing until the 1990s, when hostilities in the capital Kabul destroyed broadcasting infrastructure. Between 1996 and 2000, the Taliban government outlawed television, though some stations in areas outside Taliban control continued to broadcast. After their removal, country-wide television broadcasting was resumed beginning with the government-run channel Afghanistan National Television. It was reported that Afghanistan currently has over 200 local and international television channels, 96 in Kabul and 107 in other provinces of the country. In 2014, the country commenced a switched from analog to digital TV transmission.