DirecTV-10 is Boeing's 702 direct broadcast satellite that provides high-definition television (HDTV) for DirecTV customers in North America. Launched by International Launch Services on July 7, 2007 from Baikonur Cosmodrome in Kazakhstan with Proton M-enhanced rocket. After about two months of in-orbit testing, the satellite was transferred to its operating position at 103.0 Â ° West Longitude. This is the third DirecTV satellite launched on Proton rockets. Previous releases include DirecTV-8, which was launched on May 22, 2005, and DirecTV-5, which was launched on May 7, 2002.
DirecTV contracted with Boeing in 2004 to build three of the same model satellites 702 - 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 offered by DirecTV.
Video DirecTV-10
Technology
DirecTV-10 transmits the MPEG-4 coded signal, a compression standard more efficient than MPEG-2 that DirecTV uses for standard definition and a small number of HD channels. The use of MPEG-4 compression allows satellites to carry more channels than can use MPEG-2 compression. Receiving signals from DirecTV-10 requires a sophisticated receiver capable of decoding MPEG-4 signals, such as H21 or HR21, and 5-LNB K u /K a , such as AT-9 "Sidecar". This receiver also receives MPEG-2 channels and offers interactive services.
DirecTV-10 and DirecTV-11 are each located together with SPACEWAY-1 and SPACEWAY-2 satellites. The SPACEWAY satellite was originally designed so that the 500 MHz spectrum would be used for simple one-way broadcast and 500 MHz for 2-way broadband internet service. At DirecTV's request, Boeing disables on-board processing charges designed to provide enhanced connectivity for two-way internet services. DirecTV-10 and DirecTV-11 use this 500 MHz spectrum for simpler one-way HDTV broadcasts.
Maps DirecTV-10
B-Band Converter
Since the 500 MHz (18.3-18.8 GHz) block of frequencies used by DirecTV-10 and DirecTV-11 on downlink are not intended for DBS broadcasting, existing equipment can not accept them without B-Band Converter (BBC). DirecTV supplies BBC with all five K subplots
The satellite signal from DirecTV-10 is downconverted on the disk to the 250-750 MHz frequency range, called "K a -lo". At the receiver when required, the BBC in response to the control signal from the receiver blocked the original signal "K a -hi" between 1650-2150 MHz. Then raise the 250-750 MHz signals to this range expected by the receiver. Since this frequency range conflicts with terrestrial broadcasting frequencies, any off-the-air diplexors (OTAs) must be placed at some point after the BBC.
Specifications
DirecTV-10 uses 32 active tube propulsion and 12 backup K a -band traveling wave tube amplifier (TWTA) to broadcast national program and 55 active spot TWTA and 15 spot spots for local television service. Satellites use crooked pipe communication. It is powered by a solar array that includes 48.1 meters which consists of an ultra three solar junction solar arsenide.
Technical issues
DirecTV reported in a press release on September 14, 2007 that testing in orbit has found problems with spot spot satellite transponders used to broadcast local HDTV channels:
While DIRECTV 10 capability testing continues, it appears that some of the anticipated spot-beam capabilities may not be fully available. Investigations to determine the cause of the reduced ability and potential means to mitigate the effects are ongoing. However, we currently believe our local HD program expansion plans as previously announced will not be materially affected.
Amelioration
According to the FCC filing May 7, 2010:
"DirecTV 10 currently operates at the orbital location of 102.815 Â ° As DirecTV previously informed the Commission that satellites experienced post-launch anomalies that had limited capacity available in certain local markets DirecTV believed that it could improve this condition but would need to stop commercial services from satellites and transferring them slightly so they are not within their other operational satellites, so DirecTV intends to move DirecTV 10 to a position of 102.6 Â ° to perform restorative procedures.Within this migration, DirecTV 10 will continue to provide services to customers. However, during this migration DirecTV intends to transfer all traffic from DirecTV 10 to DirecTV-12, the latest DirecTV satellite that has just completed testing in orbit and is expected to arrive at a nominal 103 Â ° location on or about May 11, 2010. At the end of the period STA, the satellites will be in position for the chore procedure ktif to try. "
Repairs completed in mid-June and DirecTV-10 resumes its deviation back to the location set on June 24, 2010.
References
External links
- DBSTalk.com - DirecTV-10 fix threads
Source of the article : Wikipedia
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