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- Published: 22 Apr 2010
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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 and sometimes 50 ohm impedance gas filled hardline 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 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 (intermediate frequency).
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.
In the United States, service providers use the intermediate frequency ranges of 950-2150 MHz to carry the signal to the receiver. This allows for transmission of UHF band signals along the same span of coaxial wire at the same time. In some applications, (DirecTV AU9-S and AT-9) ranges the lower B-Band and upper 2250-3000 MHz, are used. Newer LNBFs in use by DirecTV referred to as SWM, use a more limited frequency range of 950-1800 MHz.
The satellite receiver or [Set-top box] 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 received signal; the receiver is then called an Integrated receiver/decoder or IRD. The cable connecting the receiver to the LNBF or LNB should be of the low loss type RG-6, quad shield RG-6 or RG-11, etc. RG-59 is not recommended for this application as it is not technically designed to carry frequencies above 950 MHz, but will work in many circumstances, depending on the quality of the coaxial wire.
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 or ISDB-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.
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.
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.
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.
Programming sources are simply the channels that provide programming for broadcast. The provider (the DTH platform) doesn’t create original programming itself. The broadcast center is the central hub of the system. At the broadcast center, the television provider receives signals from various programming sources, compresses these signals using digital compression (encryption if necessary), and sends a broadcast signal to the proper satellite.
;Channels and Satellite Fleets
;Tracking and Utilities
;General
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Name | Jamie Foxx |
---|---|
Caption | Foxx promoting Stealth in July 2005 |
Birth name | Eric Marlon Bishop |
Birth date | December 13, 1967 |
Birth place | Terrell, Texas, United States |
Medium | Stand-up, film, television, music |
Nationality | American |
Active | 1992–present |
Genre | Black comedy, Musical comedy, Satire/Political satire, Observational comedy, Character comedy, Blue comedy |
Subject | Race relations, racism, African-American culture, pop culture, human sexuality, American politics, current events, self-deprecation |
Notable work | In Living ColorJamie King on The Jamie Foxx ShowAlvin Sanders in BaitDrew 'Bundini' Brown in AliRay Charles in RayLt. Henry Purcell in StealthStaff Sgt. Sykes in JarheadCurtis Taylor Jr. in Dreamgirls |
Website | Official site |
Following these successes, Foxx appeared in Jarhead, Miami Vice, and Dreamgirls, which were box-office hits, and lifted his profile even higher as a bankable star in Hollywood. 2007 brought him the lead role in the film The Kingdom opposite Chris Cooper, Jennifer Garner and Ashraf Barhom.
In September 2007, Foxx was awarded a star on the Hollywood Walk of Fame. He said, upon receiving the honor, "[it was] one of the most amazing days of my life."
In April 2009, Foxx played the lead role in the dramatic film The Soloist.
Foxx released his second studio album, Unpredictable, in December 2005. It debuted at number two, selling 598,000 copies in its first week. The following week, the album rose to number one, selling an additional 200,000 copies. To date, the album has sold 1.98 million copies in the United States, and was certified double Platinum by the RIAA. The album also charted on the UK Albums Chart, where it peaked at number nine. Foxx became the fourth artist to have won an Academy Award for an acting role and to have achieved a number-one record album in the US. (The other three to accomplish this feat were Frank Sinatra, Bing Crosby, and Barbra Streisand.) Foxx's first single from the album, the title track "Unpredictable" (featuring Ludacris), samples "Wildflower" by New Birth. The song peaked inside the top 10 of the Billboard Hot 100 and also made the UK top 20 singles chart. The second US single from the album was "DJ Play a Love Song," which reunited Foxx with Twista. In the UK, however, the second single was "Extravaganza," which saw Foxx once again collaborate with Kanye West. He was not, however, featured in the song's music video.
At the 2006 Black Entertainment Television (BET) Awards, Foxx won Best Duet/Collaboration with Kanye West for "Gold Digger" and tied with Mary J. Blige's "Be Without You" for Video of the year. On December 8, 2006, Foxx received four Grammy nominations, which included Best R&B; Performance by a Duo or Group with Vocals for Love Changes featuring Mary J. Blige, Best R&B; Album for Unpredictable, Best Rap Performance by a Duo or Group for Georgia by Ludacris & Field Mob featuring Jamie Foxx, and Best Rap/Sung Collaboration for Unpredictable featuring Ludacris.
On January 22, 2007, Foxx was on Sirius Satellite Radio, announcing his new channel The Foxxhole. The channel features talk-radio programs, stand-up comedy albums, and music primarily by African-American performers, and features much of Foxx's own material as well. The Jamie Foxx Show, Foxx's own talk-radio variety program, airs Friday evenings on The Foxxhole, and features Johnny Mack, Speedy, The Poetess, Lewis Dix, and T.D.P., as his co-hosts. Guests include popular musicians, actors, and fellow comedians.
He recorded a song with country superstars Rascal Flatts entitled "She Goes All the Way" for their album, Still Feels Good. Foxx also performed background vocals for artist/songwriter Tank. He and The-Dream are featured on Plies' "Please Excuse My Hands." He also appeared on the remix of Ne-Yo's "Miss Independent" entitled "She Got Her Own." The track also features Fabolous. Foxx then collaborated with rapper The Game on the track "Around The World."
Foxx released his third album titled Intuition in 2008, featuring such artists as Kanye West, T.I., Lil Wayne, and T-Pain. The album's first single, "Just Like Me" featuring T.I., was promoted by a video directed by Brett Ratner and featuring an appearance by Taraji P. Henson. The second single "Blame It" featured T-Pain and became a top 5 single on the Billboard Hot 100 and a number-one single on the Billboard Hot R&B;/Hip-Hop Songs chart. The "Blame It" music video, directed by Hype Williams, features cameo appearances by Forest Whitaker, Samuel L. Jackson, Ron Howard, Quincy Jones, and Jake Gyllenhaal, among others. Foxx was also featured on T.I.'s single "Live in the Sky" from the album King.
On April 6, 2009 Foxx performed the George Strait song "You Look So Good in Love" at the George Strait Artist of the Decade All-Star Concert. Foxx has been a fan of country music for many years.
Jamie Foxx hosted the 2009 BET Awards ceremony on June 28, 2009, which featured several tributes to pop star Michael Jackson, who had died three days prior to the show. Aside from performing "Blame It" with T-Pain and "She Got Her Own" with Ne-Yo and Fabolous, Foxx opened the show with a rendition of Jackson's "Beat It" dance routine and closed the show with a cover of The Jackson 5's "I'll Be There" with Ne-Yo. Foxx stated during the ceremony, "We want to celebrate this black man. He belongs to us and we shared him with everybody else."
Foxx released his fourth album, Best Night of My Life, on December 21, 2010. The first single is "Winner", featuring Justin Timberlake and T.I.. The second single is "Living Better Now" featuring rapper Rick Ross and the third single is "Fall For Your Type" featuring rapper Drake.
Foxx has a daughter, Corinne Bishop, who was born in 1994. Foxx was spotted with the baby in Miami for New Year's Eve 2010, and it was revealed to be a girl.
Foxx performed a public service announcement for Do Something to promote food drives in local communities.
Category:1967 births Category:Actors from Texas Category:African American film actors Category:African American comedians Category:American adoptees Category:American stand-up comedians Category:American television actors Category:BAFTA winners (people) Category:Best Actor BAFTA Award winners Category:Best Actor Academy Award winners Category:Best Musical or Comedy Actor Golden Globe (film) winners Category:Living people Category:People from Linden, Texas Category:People from the Dallas – Fort Worth Metroplex Category:African American television actors Category:Grammy Award winners
This text is licensed under the Creative Commons CC-BY-SA License. This text was originally published on Wikipedia and was developed by the Wikipedia community.