satellite television is television programming
satellite television
tell by the convey of communications satellite
satellite television
and conventional by an alfresco antenna, normally a parabolical reflector by and large think of to as a satellite dish
satellite television
, and as far as household usage is concerned, a satellites receiver either in the perform of an outer set-top box
satellite television
or a satellites tuner
satellite television
module perform into a TV set
satellite television
. satellites TV tuners are besides approachable as a separate or a USB marginal to be connect to a personal computer
satellite television
. In many areas of the multinational satellites television give a widest crops of transport and services, frequently to areas that are not serviced by terrestrial
satellite television
or cable
satellite television
providers.
restrict 1 History
satellite television
2 Technology
satellite television
3 Standards
satellite television
4 Categories of usage
satellite television
4.1 operating publicize via satellite
satellite television
4.2 Television receive-only
satellite television
4.2.1 operating to chambers television
satellite television
5 See also
satellite television
6 References
satellite television
7 outer links
satellite television

The archetypal satellites television covenant was communicate from Europe
satellite television
to the Telstar
satellite television
satellites finished North America
satellite television
in 1962. The archetypal geosynchronous
satellite television
communication satellite
satellite television
, Syncom 2
satellite television
, was open in 1963. The world's archetypal commercialized communication satellite, label Intelsat I
satellite television
, was open into coetaneous loops on April 6, 1965. The archetypal federal network
satellite television
of satellites television, label Orbita
satellite television
, was perform in Soviet Union
satellite television
in 1967, and was basing on the principle of use the extremely rounded Molniya
satellite television
satellites for re-broadcasting and disclose of TV signal
satellite television
to grounds downlink
satellite television
stations. The archetypal commercialized northbound American satellites to travel television was Canada
satellite television
’s fixed Anik 1
satellite television
, which was open in 1972.
satellite television
ATS-6
satellite television
, the world's archetypal experimental educational and Direct publicize Satellite
satellite television
, was open in 1974. The archetypal Soviet better satellites to travel Direct-To-Home
satellite television
television, label Ekran
satellite television
, was open in 1976.
Technology
satellite television
satellite television
satellite television dish
satellite television
in Malaysia
satellite television
.
satellites television, seeking variant communications network by satellite, be with a exchange antenna find at an uplink
satellite television
facility. Uplink satellites dishes are very large, as much as 9 to 12 meters in diameter. The increased diameter results in more accurate deployed and increased covenant strength at the satellite. The uplink dish is level toward a special satellites and the uplinked signals are delegate indoors a special frequency range, so as to be received by one of the transponders
satellite television
adjust to that frequency crops aboard that satellite. The transponder 'retransmits' the communicate back to hide but at a different frequency strapped , typically in the C-band
satellite television
or Ku-band
satellite television
or both. The leg of the covenant path from the satellites to the obtaining hide travel is label the downlink.
decide but not least, at that place willing be a sun outage
satellite television
when the sun lines up directly behind the geostationary satellite the reception antenna is pointing to. This will happen twice a year at around midday for a two-week period and affects both the C-band and the Ku-band. The line-up swamps out all reception for a few minutes due to the sun emitting browning on the aforesaid frequencies employed by the satellite's transponders. This happens in the spring and in the fall.
The original C-Band satellites TV systems employed a Low Noise Amplifier joined to the feedhorn at the focal aim of the dish. The amplifies covenant was then fed via very costly and sometimes 50 ohm impedance gas change hardline
satellite television
coaxial cable
satellite television
to an indoor receiver or, in variant designs, fed to a downconverter for downconversion to an intermediate frequency. The channel selection was controlled, typically by a voltage change oscillator with the change voltage being fed via a segment cable to the headend. But this engineered evolved.
The advantages of using an LNB are that bargain-priced cable could be employed to interconnected the indoor receiver with the satellites TV giving and LNB, and that the technology for handling the covenant at L-Band and UHF was far bargain-priced than that for handling the covenant at C-Band frequencies. The shift to bargain-priced technology from the 50 Ohm impedance cable and N-Connectors
satellite television
of the aboriginal C-Band systems to the bargain-priced 75 Ohm technology and F-Connectors
satellite television
allowed the aboriginal satellites TV receivers to use, what be in reality, dress UHF
satellite television
TV tuners which decide the satellites television transport for drink conversion to different move intermediate frequency
satellite television
involves on 70 MHz where it was demodulated. This dress allowed the satellites television DTH
satellite television
industry to change from be a mostly hobbyist one where receivers be built in low be and accomplish systems be expensive to a far more than commercial one of masses production.
In the connects States, function providers use the intermediate frequency
satellite television
range of 950-2150 MHz to carry the covenant to the receiver. This allows for transmission of UHF strapped signals along the aforesaid span of coaxial wired at the aforesaid time. In any applications, range the move B-Band
satellite television
and apical 2250-3000 MHz, are used. Brand-new LNBFs in use by DirecTV
satellite television
think of to as SWM, use a fewer manipulate frequency crops of 2-2150 MHz.
A practical problem relating to satellites home reception is that fundamentally an LNB can only handle a single receiver. This is due to the fact that the LNB is mapping two different circular polarizations—right hand and left hand—and in the inspect of the K-band two different reception bands—lower and upper—to one and the same frequency band on the cable. Depending on which frequency a transponder is transmitting at and on what polarization it is using, the satellites receiver has to change by reversal the LNB into one of four different modes in order to receive a specific desired program on a specific transponder. This is handled by the receiver using the DiSEqC
satellite television
protocol to tamper the LNB mode. If any satellites receivers are to be connect to a only giving a so-called multiswitch
satellite television
willing have to be used in conjunction with a special write of LNB. There are besides LNBs available with a multiswitch already integrated. This problem becomes more than complicated when any receivers are to use any giving pointing to different satellites.
analogue television strewn via satellites is normally travel travel or change in NTSC
satellite television
, PAL
satellite television
, or SECAM
satellite television
television publicize standards. The analogue covenant is frequency modulated
satellite television
and is converted from an FM covenant to what is think of to as baseband
satellite television
. This baseband been the video covenant and the audio subcarrier. The audio subcarrier is further demodulated to giving a raw audio signal.
In general, digital television, include that delegate via satellites, are by and large basing on opening standards much as MPEG
satellite television
and DVB-S
satellite television
or ISDB-S
satellite television
.
There are three capital copied of satellites television usage: reception operating by the viewer, reception by local television affiliates, or reception by headends
satellite television
for distribution across tellurian cable systems
satellite television
.
Direct publicize satellite
satellite television
, also known as "Direct-To-Home" can either involves to the communications satellite themselves that deliver DBS function or the current television service. DBS systems are ordinarily think of to as "mini-dish" systems. DBS uses the apical portion of the Ku band, as surface as portions of the Ka band.
Most of the DBS systems use the DVB-S
satellite television
modular for transmission. With Pay-TV
satellite television
services, the datastream is encrypting and need branded reception equipment. While the been reception technology is similar, the Pay-TV
satellite television
technology is proprietary, frequently be of a Conditional accessing Module
satellite television
and smart card
satellite television
.
The titled Television receive-only
satellite television
, or TVRO, arose during the aboriginal days of satellite television reception to differentiate it from commercial satellite television uplink and downlink operations . This was earlier there was a DTH
satellite television
satellites television publicize industry. satellites television transport at that time be intend to be employed by cable television
satellite television
communicate instead than conventional by home viewers. satellites TV receiver systems were largely forms by hobbyists and engineers. In 1978 Microcomm, a small company initiative by covenant amateur and cook engineer H. Paul Shuch
satellite television
, announcing the first commercialized chambers satellites TV receiver. These aboriginal TVRO systems request principally on the C band
satellite television
frequencies and the giving necessitate were large; typically finished 3 meters in diameter. Consequently TVRO is frequently think of to as "big dish" or "Big grotesque Dish" satellites television.
TVRO systems tend to use larger instead than atomic satellite dish antennas, since it is more probably that the owner of a TVRO system would keep a C-band-only setup instead than a Ku band-only setup. Additional receiver boxes allowance for different copied of digital satellite signal reception, such as DVB/MPEG-2 and 4DTV
satellite television
.
Many satellite TV customers in developed television markets get their programming through a direct broadcast satellite provider. The provider selects programs and broadcasts them to subscribers as a set package. Basically, the provider’s goal is to bring dozens or even hundreds of channels to the customer's television in a form that approximates the competition from cable TV. Unlike earlier programming, the provider’s broadcast is completely digital, which means it has high picture and stereo sound quality. Early satellite television services were broadcast in C-band radio, in the 3.7 GigaHertz to 4.2 GHz frequency range. Digital broadcast satellite transmits programming in the Ku frequency range ..
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