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Satellite television
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Satellite television is television delivered by way of communications satellites, as compared to conventional terrestrial television and cable television. In many areas of the world, satellite television services supplement older terrestrial signals, providing a wider range of channels and services, including subscription-only services.
HistoryThe first satellite television signal was relayed from Europe to the Telstar satellite over North America in 1962. The first geosynchronous communication satellite, Syncom 2 was launched in 1963. The world's first commercial communication satellite, called Intelsat I (nicknamed Early Bird), was launched into synchronous orbit on April 6, 1965. The first national network of satellite television, called Orbita, was created in Soviet Union in 1967, and was based on the principle of using the highly elliptical Molniya satellite for re-broadcasting and delivering of TV signal to ground downlink stations.
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Satellite television is television delivered by way of communications satellites, as compared to conventional terrestrial television and cable television. In many areas of the world, satellite television services supplement older terrestrial signals, providing a wider range of channels and services, including subscription-only services.
HistoryThe first satellite television signal was relayed from Europe to the Telstar satellite over North America in 1962. The first geosynchronous communication satellite, Syncom 2 was launched in 1963. The world's first commercial communication satellite, called Intelsat I (nicknamed Early Bird), was launched into synchronous orbit on April 6, 1965. The first national network of satellite television, called Orbita, was created in Soviet Union in 1967, and was based on the principle of using the highly elliptical Molniya satellite for re-broadcasting and delivering of TV signal to ground downlink stations. The first domestic North American satellite to carry television was Canada’s geostationary Anik 1, which was launched in 1972 . ATS-6, the world's first experimental educational and Direct Broadcast Satellite, was launched in 1974. The first Soviet geostationary satellite to carry Direct-To-Home television, called Ekran, was launched in 1976.
TechnologySatellites used for television signals are generally in either naturally highly elliptical (with inclination of +/-63.4 degrees and orbital period of about 12 hours) or geostationary orbit 37,000 km (22,300 miles) above the earth’s equator.
Satellite television, like other communications relayed by satellite, starts with a transmitting antenna located at an uplink facility. Uplink satellite dishes are very large, as much as 9 to 12 meters (30 to 40 feet) in diameter. The increased diameter results in more accurate aiming and increased signal strength at the satellite. The uplink dish is pointed toward a specific satellite and the uplinked signals are transmitted within a specific frequency range, so as to be received by one of the transponders tuned to that frequency range aboard that satellite. The transponder 'retransmits' the signals back to Earth but at a different frequency band (a process known as translation, used to avoid interference with the uplink signal), typically in the C-band (4–8 GHz) or Ku-band (12–18 GHz) or both. The leg of the signal path from the satellite to the receiving Earth station is called the downlink.
A typical satellite has up to 32 transponders for Ku-band and up to 24 for a C-band only satellite, or more for hybrid satellites. Typical transponders each have a bandwidth between 27 MHz and 50 MHz. Each geo-stationary C-band satellite needs to be spaced 2 degrees from the next satellite (to avoid interference). For Ku the spacing can be 1 degree. This means that there is an upper limit of 360/2 = 180 geostationary C-band satellites and 360/1 = 360 geostationary Ku-band satellites. C-band transmission is susceptible to terrestrial interference while Ku-band transmission is affected by rain (as water is an excellent absorber of microwaves at this particular frequency).
The downlinked satellite signal, quite weak after traveling the great distance (see inverse-square law), is collected by a parabolic receiving dish, which reflects the weak signal to the dish’s focal point. Mounted on brackets at the dish's focal point is a device called a feedhorn. This feedhorn is essentially the flared front-end of a section of waveguide that gathers the signals at or near the focal point and 'conducts' them to a probe or pickup connected to a low-noise block downconverter or LNB. The LNB amplifies the relatively weak signals, filters the block of frequencies in which the satellite TV signals are transmitted, and converts the block of frequencies to a lower frequency range in the L-band range. The evolution of LNBs was one of necessity and invention.
The original C-Band satellite TV systems used a Low Noise Amplifier connected to the feedhorn at the focal point of the dish. The amplified signal was then fed via very expensive 50 Ohm impedance coaxial cable to an indoor receiver or in other designs fed to a downconverter (a mixer and a voltage tuned oscillator with some filter circuitry) for downconversion to an intermediate frequency. The channel selection was controlled, typically by a voltage tuned oscillator with the tuning voltage being fed via a separate cable to the headend. But this simple design evolved.
Designs for microstrip based converters for Amateur Radio frequencies were adapted for the 4 GHz C-Band. Central to these designs was concept of block downconversion of a range of frequencies to a lower, and technologically more easily handled block of frequencies.
The advantages of using an LNB are that cheaper cable could be used to connect the indoor receiver with the satellite TV dish and LNB, and that the technology for handling the signal at L-Band and UHF was far cheaper than that for handling the signal at C-Band frequencies. The shift to cheaper technology from the 50 Ohm impedance cable and N-Connectors of the early C-Band systems to the cheaper 75 Ohm technology and F-Connectors allowed the early satellite TV receivers to use, what were in reality, modified UHF TV tuners which selected the satellite television channel for down conversion to another lower intermediate frequency centered on 70 MHz where it was demodulated. This shift allowed the satellite television DTH industry to change from being a largely hobbyist one where receivers were built in low numbers and complete systems were expensive (costing thousands of Dollars) to a far more commercial one of mass production.
Direct broadcast satellite dishes are fitted with an LNBF, which integrates the feedhorn with the LNB.
The satellite receiver demodulates and converts the signals to the desired form (outputs for television, audio, data, etc.). Sometimes, the receiver includes the capability to unscramble or decrypt; the receiver is then called an Integrated receiver/decoder or IRD. The cable connecting the receiver to the LNBF or LNB must be of the low loss type RG-6, quad shield RG-6 or RG-11, etc. It cannot be standard RG-59.
(A new form of satellite antenna, which does not use a directed parabolic dish and can be used on a mobile platform such as a vehicle, was recently announced by the University of Waterloo. )
StandardsAnalog television distributed via satellite is usually sent scrambled or unscrambled in NTSC, PAL, or SECAM television broadcast standards. The analog signal is frequency modulated and is converted from an FM signal to what is referred to as baseband. This baseband comprises the video signal and the audio subcarrier(s). The audio subcarrier is further demodulated to provide a raw audio signal.
If the signal is a digitized television signal or multiplex of signals, it is typically QPSK.
In general, digital television, including that transmitted via satellites, are generally based on open standards such as MPEG and DVB-S.
The conditional access encryption/scrambling methods include BISS, Conax, Digicipher, Irdeto, Nagravision, PowerVu, Viaccess, Videocipher, and VideoGuard. Many conditional access systems have been compromised.
Categories of usageThere are three primary types of satellite television usage: reception direct by the viewer, reception by local television affiliates, or reception by headends for distribution across terrestrial cable systems.
Direct to the viewer reception includes direct broadcast satellite or DBS and television receive-only or TVRO, both used for homes and businesses including hotels, etc.
Direct broadcast via satelliteDirect broadcast satellite, (DBS) also known as "Direct-To-Home" is a relatively recent development in the world of television distribution. “Direct broadcast satellite” can either refer to the communications satellites themselves that deliver DBS service or the actual television service. DBS systems are commonly referred to as "mini-dish" systems. DBS uses the upper portion of the Ku band.
Modified DBS systems can also run on C-band satellites and have been used by some networks in the past to get around legislation by some countries against reception of Ku-band transmissions.
Most of the DBS systems use the DVB-S standard for transmission. With Pay-TV services, the datastream is encrypted and requires proprietary reception equipment. While the underlying reception technology is similar, the Pay-TV technology is proprietary, often consisting of a Conditional Access Module and smart card.
This measure assures satellite television providers that only authorised, paying subscribers have access to Pay TV content but at the same time can allow free-to-air (FTA) channels to be viewed even by the people with standard equipment (DBS receivers without the Conditional Access Modules) available in the market.
Television receive-onlyThe term Television receive-only, or TVRO, arose during the early days of satellite television reception to differentiate it from commercial satellite television uplink and downlink operations (transmit and receive). This was before there was a DTH satellite television broadcast industry. Satellite television channels at that time were intended to be used by cable television networks rather than received by home viewers. Satellite TV receiver systems were largely constructed by hobbyists and engineers. These TVRO system operated mainly on the C band frequencies and the dishes required were large; typically over ten feet in diameter. Consequently TVRO is often referred to as "big dish" or "Big Ugly Dish" (BUD) satellite television.
TVRO systems are designed to receive analog and digital satellite feeds of both television or audio from both C-band and Ku-band transponders on FSS-type satellites. The higher frequency Ku-band systems tend to be Direct To Home systems and can use a smaller dish antenna because of the higher power transmissions and greater antenna gain.
TVRO systems tend to use larger rather than smaller satellite dish antennas, since it is more likely that the owner of a TVRO system would have a C-band-only setup rather than a Ku band-only setup. Additional receiver boxes allow for different types of digital satellite signal reception, such as DVB/MPEG-2 and 4DTV.
The narrow beam width of a normal parabolic satellite antenna means it can only receive signals from a single satellite at a time. Simulsat or the Vertex-RSI TORUS, is a quasi-parabolic satellite earthstation antenna that is capable of receiving satellite transmissions from 35 or more C- and Ku-band satellites simultaneously.
Satellite television by region and countryAfricaSouth African-based Multichoice's DStv is the main digital satellite television provider in sub-Saharan Africa, broadcasting principally in English, but also in Portuguese, German and Afrikaans. Canal Horizons, owned by France's Canal+, is the main provider in French-speaking Africa. Another entrant into the satellite television circuit in Africa is MyTvAfrica, a subsidiary of Dubai based Strong Technologies. Satellite television has been far more successful in Africa than cable, primarily because the infrastructure for cable television does not exist and would be expensive to install since majority of Africans cannot afford paid cable television. Furthermore, maintaining a cable network is expensive due to the need to cover larger and more sparsely populated areas though there are some terrestrial pay-TV and MMDS services.
The launch of Free2view has made satellite TV available to the masses in Africa. Free2view currently broadcasts MSNBC as its exclusive news channel and is about to roll out additional channels.
GTV, a British-based company, has become the second in sub-saharan Africa providing digital satellite television with the focus first on Kenya Uganda, Tanzania, Zimbabwe, Congo ETC.
NigeriaTraditionally DStv had held a monopoly over Nigeria's Satellite television sector but a new company, HiTV is starting to compete in this sector.
SudanSudan TV, the government-owned national network, is available by satellite as well as broadcast.
The AmericasCanadaIn Canada, the two legal DBS services available are Bell ExpressVu and Star Choice. The CRTC has refused to license American satellite services, but nonetheless hundreds of thousands (up to a million by some estimates) of Canadians access or have accessed American services — usually these services have to be billed to an American address and are paid for in U.S. dollars, although some viewers receive American signals through pirate decryption. Whether such activity is grey market or black market is the source of often heated debate between those who would like greater choice and those who argue that the protection of Canadian firms and Canadian culture is more important.
In October 2004, Quebec judge Danièle Côté ruled Canada's Radiocommunication Act to be in direct violation of the Canadian Charter of Rights and Freedoms, insofar as it bans reception of unlicensed foreign television services. The judgment gave the federal government a one-year deadline to remedy this breach of the Constitution. However, this contradicts prior Supreme Court of Canada decisions and, at last word in late 2004, was expected to be appealed.
In addition, Canadian satellite providers continue to be plagued by the unquestionably black market devices which "pirate" or "steal" their signals as well as by a number of otherwise completely lawful devices which can be reprogrammed to receive pirate TV.
One cable TV CEO (Karl Péladeau of Québecor, which owns Vidéotron) is on public record as demanding conditions be placed on the CRTC license issued to Bell ExpressVu, due to BEV’s reputation for vastly inferior security compared to its cable rivals and Shaw Cable–owned Star Choice.
Although there are no official statistics, the use of American satellite services in Canada appears to be declining as of 2004.
Some would claim that this is probably due to a combination of increasingly aggressive police enforcement and an unfavourable exchange rate between the Canadian and U.S. currencies. As the U.S. dollar has been declining as of 2005 versus other international currencies, the decline in DirecTV viewership in Canada may well be related not to a cost difference as much as to the series of smart card swaps which have rendered the first three generations of DirecTV access cards (F, H and HU) all obsolete.
Latin AmericaLatin America’s main satellite system are SKY Latin America, which has approximately 1.4 million subscribers in each of Brazil and Mexico and DirecTV Latin America, which provides service to the rest of the Americas, with a total of approximately 1.3 million subscribers. Pay-TV is not popular among Latin American because fees are expensive in PPP terms.
The service offered in Brazil includes Digital TV with full Dolby Digital surround support, mts and multiple subtitle options, a first for the Brazilian market. A recent update to Sky's services in Brazil is Sky+ which allows the customer to record a program while watching another one, this service is however very expensive resulting in very few clients subscribing to this add-on.
United States
Currently, there are two primary satellite television providers of subscription based service available to United States consumers: Dish Network and DirecTV.
Over the past three decades, various U.S. satellite services have come and gone or combined to form the current primary services. In 1975 RCA created Satcom 1, the first satellite built especially for use by the then three national television networks. Later that same year, HBO leased a transponder on Satcom 1 and began transmission of television programs via satellite to cable systems. Owners of cable systems paid $10,000 to install 3-meter dishes to receive TV signal in C-band.
In 1976 Taylor Howard built an amateur system, which consisted of a converted military surplus radar dish and a satellite receiver designed and built by Howard, for home satellite reception. Taylor's system could be used for receiving TV programs both from American and Soviet communication satellites. In 1977 Pat Robertson launched the first satellite-delivered basic cable service called the CBN Cable Network. In 1979, the Satellite Home Viewers Act allowed homeowners in the US to own and operate their own home satellite system, consisting of C-band equipment from a multitude of manufacturers who were making parts for systems such as Taylor Howard's, and began a large controversy of which channels could be received by whom.
USSB was a direct-to-home service founded in 1981. In the early 1990s they partnered with Hughes and continued operation until purchased in 1998 by DirecTV.
In 1991 Primestar launched as the first North American DBS service. Hughes’s DirecTV, the first national high-powered upper Ku-band DBS system, went online in 1994. The DirecTV system became the new delivery vehicle for USSB. News Corporation currently holds a 38% stake, which it is in the process of selling to Liberty Media. In 1996, EchoStar’s Dish Network went online in the United States and has gone on to similar success as DirecTV’s primary competitor. The AlphaStar service launched in 1996 and went into bankruptcy in 1997. Dominion Video Satellite Inc's Sky Angel also went online in the United States in 1996 with its DBS service geared towards "faith and family". Primestar sold its assets to Hughes in 1999 and switched from DBS to an IPTV platform.
In 2004, Cablevision’s Voom service went online, specifically catering to the emerging market of HDTV owners and aficionados, but folded in April 2005. The service’s “exclusive” high-definition channels were migrated to the Dish Network system. Commercial DBS services are the primary competition to cable television service, although the two types of service have significantly different regulatory requirements (for example, cable television has public access requirements, and the two types of distribution have different regulations regarding carriage of local stations).
The majority of ethnic-language broadcasts in North America are carried on Ku band free-to-air. The largest concentration of ethnic programming is on Galaxy 25 at 97° W. Pittsburgh International Telecommunications and GlobeCast World TV offers a mix of free and pay-TV ethnic channels in the internationally-standard DVB-S format, as do others. Home2US Communications Inc. also offers several ethnic channels on AMC-4 at 101° W, as well as other free and pay-TV channels. Several U.S.-English language network affiliates (representing CBS, NBC, ABC, PBS, FOX, the CW (formerly the WB and UPN), ION Network and MyNetworkTV) are available as free-to-air broadcasts, as are the three U.S.-Spanish language networks. The number of free-to-air specialty channels is otherwise rather limited. Specific FTA offerings tend to appear and disappear rather often and typically with little or no notice, although sites such as do track the changing availability of both free and pay channels worldwide.
AsiaBangladeshThere are several satellite providers in Bangladesh. The main ones are listed below:
- Bangla Vision
- NTV
- RTV
- ATN Bangla
- Channel I
- Channel 1
- Boishaki TV
- ETV
- DESH TV
- Diganta Television
- Islamic TV
- STVUS
IndiaIn India there are more than 300 TV Channels are operating.
India has the indigenously built INSAT series satellites from Indian Space Research Organisation along with some private operators . INSAT 4A, INSAT-2E, INSAT-3C and INSAT-3E carry multiple channels for Indian television viewers.1. Netherlands-based SES Global-owned NSS 6, Thaicom-2 and Telstar 10 are the other major private satellites over India. Notable service providers offering a bouquet of multiple channels are state-owned Doordarshan, News Corporation owned STAR TV, Sony owned Sony Entertainment Television, Sun Network and Zee TV.
DD Direct Plus, DishTV and Tata Sky are the three major commercial service providers of Satellite Television in India.
Sun Network has also entered into the Commercial service provider of Satellite TV in India.
KazakhstanThe first salellite TV channel in Kazakstan, CaspioNet, was launched by the Khabar news agency in 2002.
MalaysiaMalaysia's sole satellite television operator, Measat Broadcast Network Systems (a subsidiary of Astro All Asia Networks plc) launched Astro in 1996. It currently holds exclusive rights from the Malaysian government to offer satellite television broadcasting services in the country through the year 2017.
JapanThe medium-scale Broadcasting Satellite for Experimental Purposes (BSE) was planned by Ministry of Posts and Telecommunications (MOPT) and developed by the National Space Development Agency of Japan since 1974. After that, the first Japanese experimental broadcasting satellite, called BSE or Yuri, was launched in 1978. NHK started experimental broadcasting of TV program using BS-2a satellite on May, 1984.
The satellite BS-2a was launched in preparation for the start of full scale 2-channel broadcasts. Broadcasting Satellite BS-2a was the first national DBS (direct broadcasting satellite), transmitting signals directly into the home of TV viewers. Attitude control of the satellite was conducted using the 3 axial method (zero momentum), and design life was 5 years. The TV transponder units are designed to sufficiently amplify transmitted signals to enable reception by small, 40 or 60 cm home-use parabolic antennas. The satellite was equipped with 3 TV transponders (including reserve units). However, one transponder malfunctioned 2 months after launch (March 23, 1984) and a second transponder malfunctioned 3 months after launch (May 3, 1984). So, the scheduled satellite broadcasting had to be hastily adjusted to test broadcasting on a single channel.
Later, NHK started regular service and experimental HDTV broadcasting using BS-2b on June, 1989. Some Japanese producers of home electronic consumer devices began to deliver TVsets, VCRs and even home acoustic systems equipped by built-in satellite tuners or receivers. Such electronic goods had a specific BS logo.
On April, 1991, Japanese company JSB started pay TV service while BS-3 communication satellite was in use. In 1996 total number of households that receive satellite broadcasting exceeded 10 million.
The modern two satellite systems in use in Japan are BSAT and JCSAT; the modern WOWOW Broadcasting Satellite digital service uses BSAT satellites, while other system of digital TV broadcasting SKY PerfecTV! uses JCSAT satellites.
PakistanIn the recent years, there has been a lot of investment in television industry in Pakistan. There are more than 90 Satellite channels operating directly inside Pakistan and about 40 operating their broadcasting from Dubai, Thailand, Bankok and UK.
PhilippinesDream Satellite TV is pay DTH service of Philippine Multimedia Service Inc.(PMSI).
Thailand and Media in Thailand
TrueVisions is the leading pay TV service of Thailand which operate cable TV in Bangkok and satellite TV across the country. TrueVisions is owned by True Corporation.
AustraliasiaAustraliaSatellite television in Australia has proven to be a far more feasible option than cable television, due to the vast distances between population centres, although this explanation seems to contradict the rationale behind the relatively high cable television penetration rate in Canada, a country with an even larger distance between population centres and lower population density than Australia. The first service to come online in Australia was Galaxy, which was later taken over by Cable Television giant Foxtel, which now operates both cable and satellite services to all state capital cities (except Darwin and Hobart) and the whole of Western Australia. Its main metropolitan rival was Optus Vision, while rural areas are served by Austar, both of which just rebroadcast Foxtel as of 2005. In 2006 SelecTV began operating, aiming at providing comparatively low cost packages and catering to specialised market segments.
New Zealand In New Zealand, SKY Network Television offers multichannel digital satellite TV, in addition to its non-digital terrestrial UHF service. The newly released Freeview service is also available on the Optus D1 satellite, as well as a High Definition digital terrestrial service. The current FTA service broadcasts all of New Zealand's national free-to-air services with the exception of the Prime channel which is owned by SKY TV.
EuropeContinental Western EuropeIn Europe, DBS satellite services are found mainly on Astra satellites and Hotbird (operated by Eutelsat.) BSkyB (known as Sky) serves the UK. Sky Italia, Canal Digitaal and UPC being the main providers in Italy, the Netherlands and Central Europe.
The overall market share of DBS satellite services in 2004 was 21.4% of all TV homes, however this highly varies from country to country. For example, in Germany, with many free-to-air TV-stations, DBS market share is almost 40%, and in Belgium and the Netherlands, it’s only about 7%, due to the widespread cable networks with exclusive content.
Russian FederationThe first Soviet communication satellite, called Molniya, was launched in 1965. By November, 1967 the national system of satellite television, called Orbita was deployed. The system consisted of 3 highly elliptical Molniya satellites, Moscow-based ground uplink facilities and about 20 downlink stations, located in cities and towns of remote regions of Siberia and Far East. Each station had a 12-meter receiving parabolic antenna and transmitters for re-broadcasting TV signal to local householders.
However, a large part of Soviet central regions were still not covered by transponders of Molniya satellites.
By 1976 Soviet engineers developed a relatively simple and inexpensive system of satellite television (especially for Central and Northern Siberia). It included geostationary satellites called Ekran equipped with powerful 300 W UHF transponders, a broadcasting uplink station and various simple receiving stations located in various towns and villages of Siberian region. The typical receiving station, also called Ekran, represented itself as a home-use analog satellite receiver equipped with simple Yagi-Uda antenna. Later, Ekran satellites were replaced by more advanced Ekran-M series satellites.
In 1979 Soviet engineers developed Moskva (or Moscow) system of broadcasting and delivering of TV signal via satellites. New type of geostationary communication satellites, called Gorizont, were launched. They were equipped by powerful onboard transponders, so the size of receiving parabolic antennas of downlink stations was reduced to 4 and 2.5 meters (in comparison of early 12- meter dishes of standard orbital downlink stations).
By 1989 an improved version of Moskva system of satellite television has been called Moskva Global'naya (or Moscow Global). The system included a few geostationary Gorizont and Express type of communication satellites. TV signal from Moscow Global’s satellites could be received in any country of planet except Canada and North-West of the USA.
Modern Russian satellite broadcasting services based on powerful geostationary buses such as Gals, Express, Yamal and Eutelsat which provide a large quantity of free-to-air television channels to millions of householders. Pay-TV is growing in popularity amongst Russian TV viewers. The NTV Russia news company, owned by Gazprom, broadcasts the NTV Plus package to 560,000 households, reaching over 1.5 million viewers.
United Kingdom and IrelandThe first commercial DBS service in the United Kingdom, Sky Television, was launched in 1989 and used the newly launched ASTRA satellite, providing 4 analogue TV channels. The channels and subsequent VideoCrypt video encryption system used the existing PAL broadcast standard. This gave Sky a distinct advantage over the winner of the UK state DBS licence, BSB.
In the following year, after many delays, BSB was launched, broadcasting five channels|Now]], Galaxy, The Movie Channel, The Power Station and The Sports Channel) in D-MAC format and using the EuroCypher video encryption system which was based heavily on the General Instruments VideoCipher system used in the USA. While the BSB system was technologically more advanced than the PAL system and one of the main selling points of the BSB offering was the Squarial, an expensive flat plate antenna and LNB. Sky's system used conventional and cheap dish and LNB technology.
The competition between the two companies was fierce and bidding wars over the UK rights to movies. Sky kept costs to a bare minimum, operating from an industrial park in Isleworth in West London. BSB had expensive offices in London. The two services subsequently merged to form British Sky Broadcasting (BSkyB) though the new BSkyB was really Sky. The technologically more advanced BSB D-MAC/EuroCypher system was gradually replaced with Sky's VideoCrypt video encryption system.
In 1994 17% of the group was floated on the London Stock Exchange (with ADRs listed on the New York Stock Exchange), and Rupert Murdoch’s News Corporation owns a 35% stake.
By 1999, following the launch of several more satellites (at 19.2°E by SES Astra, the number of channels had increased to around 60 and BSkyB launched the first subscription-based digital television platform in the UK, offering a range of 300 channels broadcast from the | |
