fbpx
Wikipedia

T10 (satellite)

T10 (formerly DirecTV-10) is a Boeing model 702 direct broadcast satellite that provides high-definition television (HDTV) to DirecTV subscribers in North America.[1] It was launched by International Launch Services on July 7, 2007 from the Baikonur Cosmodrome in Kazakhstan aboard an Enhanced Proton Breeze-M rocket.[2] After about two months of in-orbit testing, the satellite was moved to its operating position at 103.0° west longitude.[3] This was the third DirecTV satellite launched on a Proton rocket. Prior launches include T8, which was launched on May 22, 2005, and T5, which was launched on May 7, 2002. The satellite was renamed to T10 in 2017.[4]

T10
OperatorDirecTV
COSPAR ID2007-032A
SATCAT no.31862
Mission durationElapsed: 16 years, 10 months, 17 days
Spacecraft properties
BusBSS-702
ManufacturerBoeing
Start of mission
Launch dateJuly 6, 2007 (2007-07-06)
RocketProton-M/Briz-M
Launch siteBaikonur 200/39
ContractorILS
Orbital parameters
Reference systemGeocentric
RegimeGeostationary
Longitude103.0° West
Transponders
Capacity500 MHz
 

DirecTV contracted with Boeing in 2004 to build three identical 702 model satellites — DirecTV-10, 11 and 12. DirecTV-11 was launched on March 19, 2008 and DirecTV-12 was launched on December 29, 2009. The satellites were purchased to significantly increase the number of national and local HDTV channels DirecTV offers.[5] All satellites have since been renamed to the T-suffix.

Technology edit

 
DirecTV AU9-S 5-LNB "Slimline" satellite dish
 
DirecTV AT-9 5-LNB "Sidecar" satellite dish

T10 transmits MPEG-4 encoded signals, a compression standard which is more efficient than MPEG-2 which DirecTV uses for standard definition and a small number of HD channels. The use of MPEG-4 compression allows the satellite to carry significantly more channels than it could using MPEG-2 compression. Receiving signals from DirecTV-10 requires an advanced receiver capable of decoding MPEG-4 signals, such as the H21 or HR21, and a 5-LNB Ku/Ka dish, such as the AT-9 "Sidecar". These receivers also receive MPEG-2 channels and offer interactive services.

T10 was co-located with the SPACEWAY-1 satellite until the latter was decommissioned in 2020. The SPACEWAY satellites were originally designed so that 500 MHz of spectrum would be used for simple one-way broadcasting and 500 MHz for a broadband 2-way internet service. At the request of DirecTV, Boeing disabled the on-board processing payload designed to deliver enhanced connectivity for the 2-way internet service. T10 and T11 use this 500 MHz of spectrum for yet more simple one-way broadcast HDTV.

B-Band converter edit

 
B-Band Converters Connected to DirecTV HR20-700 Receiver

Since the 500 MHz frequency block (18.3-18.8 GHz) used by T10 and T11 on downlink were not intended for DBS broadcasting, existing equipment cannot receive them without a B-Band Converter (BBC). DirecTV supplies BBCs with all 5-LNB Ku/Ka-band dish systems.

The satellite signal from T10 is downconverted at the dish to the frequency range of 250-750 MHz, called "Ka-lo". At the receiver when necessary, the BBC in response to a control signal from the receiver blocks any original "Ka-hi" signals between 1650-2150 MHz. Then up-converts the 250-750 MHz signals to this range which is expected by current receivers. Because this frequency range conflicts with terrestrial broadcast frequencies, any off-the-air (OTA) diplexors[6] must be placed at some point after the BBC.

Specifications edit

T10 uses 32 active and 12 spare Ka-band Traveling wave tube amplifiers (TWTA) to broadcast national programming and 55 active and 15 spare spot beam TWTAs for local television services. The satellite uses bent pipe communications. It is powered by a solar array spanning 48.1 meters that consists of ultra triple junction gallium arsenide solar cells.[1]

Technical problems edit

DirecTV reported in a press release on September 14, 2007 that in-orbit testing had uncovered problems with the satellite's spot beam transponders used to broadcast local HDTV channels:

While testing of DIRECTV 10's capability continues, it appears that a portion of the anticipated spot-beam capability may not be fully available. The investigation to determine the cause of the reduced capability and potential means to mitigate its effect is on-going. However, we currently believe our planned expansion of HD local programming as previously announced will not be materially affected. [7]

Amelioration edit

According to a May 7, 2010 FCC filing:

"DirecTV 10 is currently operating at the 102.815° orbital location. As DirecTV has previously informed the Commission, that satellite suffered a post launch anomaly that has limited the capacity available in certain local markets. DirecTV believes that it can ameliorate this condition, but will need to discontinue commercial service from the satellite and relocate it slightly so that it is not within the cluster of its other operational satellites. Accordingly, DirecTV intends to move DirecTV 10 to the 102.6° position to conduct the restorative procedure. During this migration, DirecTV 10 will continue to provide service to subscribers. However, over the course of this migration, DirecTV intends to transfer all traffic from DirecTV 10 to DirecTV-12, DirecTV's newest satellite which has just completed in-orbit testing and is expected to arrive at the nominal 103° location on or about May 11, 2010. At the conclusion of the STA period, the satellite will be in a position for the corrective procedure to be attempted."[8]

The fixes were completed in mid June and T10 (then known as DirecTV-10) completed its drift back to its assigned location on June 24, 2010.

References edit

  1. ^ a b (PDF). Archived from the original (PDF) on 2008-07-06. Retrieved 2007-05-22.
  2. ^ Spaceflight Now | Tracking Station | Worldwide launch schedule August 11, 2013, at the Wayback Machine
  3. ^ "Spaceway 1 & DirecTV 10/12 at 102.8°W". LyngSat.com. Retrieved November 30, 2022.
  4. ^ "DIRECTV 10 Norad ID: 31862". isstracker.pl. Retrieved November 30, 2022.
  5. ^ Gunter's Space Page - Information on Launch vehicles, Satellites, Space Shuttle and Astronautics
  6. ^ Zinwell switch with some BBC information
  7. ^ DIRECTV 10 In-Orbit Testing Underway 2011-07-16 at the Wayback Machine DirecTV Press Release September 14, 2007
  8. ^ DirecTV STA request May 7, 2010

External links edit

  • DBSTalk.com - DirecTV-10 repair thread

satellite, formerly, directv, boeing, model, direct, broadcast, satellite, that, provides, high, definition, television, hdtv, directv, subscribers, north, america, launched, international, launch, services, july, 2007, from, baikonur, cosmodrome, kazakhstan, . T10 formerly DirecTV 10 is a Boeing model 702 direct broadcast satellite that provides high definition television HDTV to DirecTV subscribers in North America 1 It was launched by International Launch Services on July 7 2007 from the Baikonur Cosmodrome in Kazakhstan aboard an Enhanced Proton Breeze M rocket 2 After about two months of in orbit testing the satellite was moved to its operating position at 103 0 west longitude 3 This was the third DirecTV satellite launched on a Proton rocket Prior launches include T8 which was launched on May 22 2005 and T5 which was launched on May 7 2002 The satellite was renamed to T10 in 2017 4 T10OperatorDirecTVCOSPAR ID2007 032ASATCAT no 31862Mission durationElapsed 16 years 10 months 17 daysSpacecraft propertiesBusBSS 702ManufacturerBoeingStart of missionLaunch dateJuly 6 2007 2007 07 06 RocketProton M Briz MLaunch siteBaikonur 200 39ContractorILSOrbital parametersReference systemGeocentricRegimeGeostationaryLongitude103 0 WestTranspondersCapacity500 MHz DirecTV contracted with Boeing in 2004 to build three identical 702 model satellites DirecTV 10 11 and 12 DirecTV 11 was launched on March 19 2008 and DirecTV 12 was launched on December 29 2009 The satellites were purchased to significantly increase the number of national and local HDTV channels DirecTV offers 5 All satellites have since been renamed to the T suffix Contents 1 Technology 2 B Band converter 3 Specifications 4 Technical problems 4 1 Amelioration 5 References 6 External linksTechnology edit nbsp DirecTV AU9 S 5 LNB Slimline satellite dish nbsp DirecTV AT 9 5 LNB Sidecar satellite dish T10 transmits MPEG 4 encoded signals a compression standard which is more efficient than MPEG 2 which DirecTV uses for standard definition and a small number of HD channels The use of MPEG 4 compression allows the satellite to carry significantly more channels than it could using MPEG 2 compression Receiving signals from DirecTV 10 requires an advanced receiver capable of decoding MPEG 4 signals such as the H21 or HR21 and a 5 LNB Ku Ka dish such as the AT 9 Sidecar These receivers also receive MPEG 2 channels and offer interactive services T10 was co located with the SPACEWAY 1 satellite until the latter was decommissioned in 2020 The SPACEWAY satellites were originally designed so that 500 MHz of spectrum would be used for simple one way broadcasting and 500 MHz for a broadband 2 way internet service At the request of DirecTV Boeing disabled the on board processing payload designed to deliver enhanced connectivity for the 2 way internet service T10 and T11 use this 500 MHz of spectrum for yet more simple one way broadcast HDTV B Band converter edit nbsp B Band Converters Connected to DirecTV HR20 700 Receiver Since the 500 MHz frequency block 18 3 18 8 GHz used by T10 and T11 on downlink were not intended for DBS broadcasting existing equipment cannot receive them without a B Band Converter BBC DirecTV supplies BBCs with all 5 LNB Ku Ka band dish systems The satellite signal from T10 is downconverted at the dish to the frequency range of 250 750 MHz called Ka lo At the receiver when necessary the BBC in response to a control signal from the receiver blocks any original Ka hi signals between 1650 2150 MHz Then up converts the 250 750 MHz signals to this range which is expected by current receivers Because this frequency range conflicts with terrestrial broadcast frequencies any off the air OTA diplexors 6 must be placed at some point after the BBC Specifications editT10 uses 32 active and 12 spare Ka band Traveling wave tube amplifiers TWTA to broadcast national programming and 55 active and 15 spare spot beam TWTAs for local television services The satellite uses bent pipe communications It is powered by a solar array spanning 48 1 meters that consists of ultra triple junction gallium arsenide solar cells 1 Technical problems editDirecTV reported in a press release on September 14 2007 that in orbit testing had uncovered problems with the satellite s spot beam transponders used to broadcast local HDTV channels While testing of DIRECTV 10 s capability continues it appears that a portion of the anticipated spot beam capability may not be fully available The investigation to determine the cause of the reduced capability and potential means to mitigate its effect is on going However we currently believe our planned expansion of HD local programming as previously announced will not be materially affected 7 Amelioration edit According to a May 7 2010 FCC filing DirecTV 10 is currently operating at the 102 815 orbital location As DirecTV has previously informed the Commission that satellite suffered a post launch anomaly that has limited the capacity available in certain local markets DirecTV believes that it can ameliorate this condition but will need to discontinue commercial service from the satellite and relocate it slightly so that it is not within the cluster of its other operational satellites Accordingly DirecTV intends to move DirecTV 10 to the 102 6 position to conduct the restorative procedure During this migration DirecTV 10 will continue to provide service to subscribers However over the course of this migration DirecTV intends to transfer all traffic from DirecTV 10 to DirecTV 12 DirecTV s newest satellite which has just completed in orbit testing and is expected to arrive at the nominal 103 location on or about May 11 2010 At the conclusion of the STA period the satellite will be in a position for the corrective procedure to be attempted 8 The fixes were completed in mid June and T10 then known as DirecTV 10 completed its drift back to its assigned location on June 24 2010 References edit a b Boeing Directv 10 specifications PDF Archived from the original PDF on 2008 07 06 Retrieved 2007 05 22 Spaceflight Now Tracking Station Worldwide launch schedule Archived August 11 2013 at the Wayback Machine Spaceway 1 amp DirecTV 10 12 at 102 8 W LyngSat com Retrieved November 30 2022 DIRECTV 10 Norad ID 31862 isstracker pl Retrieved November 30 2022 Gunter s Space Page Information on Launch vehicles Satellites Space Shuttle and Astronautics Zinwell switch with some BBC information DIRECTV 10 In Orbit Testing Underway Archived 2011 07 16 at the Wayback Machine DirecTV Press Release September 14 2007 DirecTV STA request May 7 2010External links edit nbsp Spaceflight portal DBSTalk com DirecTV 10 repair thread Retrieved from https en wikipedia org w index php title T10 satellite amp oldid 1141903088, wikipedia, wiki, book, books, library,

article

, read, download, free, free download, mp3, video, mp4, 3gp, jpg, jpeg, gif, png, picture, music, song, movie, book, game, games.