| 词条 | Teledesic |
| 释义 |
The commercial failure of the similar Iridium and Globalstar ventures (composed of 66 and 48 operational satellites respectively) and other systems, along with bankruptcy protection filings, were primary factors in halting the project, and Teledesic officially suspended its satellite construction work on October 1, 2002.[3] Teledesic was notable for gaining early funding from cellular pioneer Craig McCaw, Microsoft co-founder Bill Gates, and Saudi prince Alwaleed bin Talal,[4] and for achieving a radio frequency spectrum allocation in the Ka-band for non-geostationary fixed satellite services. DescriptionThe satellites were three-axis stabilized with a faceted antenna on the bottom and a large articulated solar panel on top. The spacecraft was designed to be compatible with over 20 different launch vehicles to permit launch option flexibility. The satellites were to be launched into a 700 km circular, near-polar (98.2°) Sun-synchronous orbit. The initial rollout was to include 12 orbit planes with 24 spacecraft in each plane. The antenna footprint for each satellite was to be about 700 km. Teledesic has 288 satellites in 12 LEO orbits, each at an altitude of 1315 kln. Teledesic T1A demonstration satellite for the Teledesic constellation, originally labeled Broadband Advanced Technologies Satellite ("BATSAT"),[5] and later renamed "Teledesic T1", was launched on a Pegasus-XL launch vehicle in February 1998. The satellite differed in size and design from the anticipated satellite for the final constellation, but was designed to support two-way communications at speeds up to E1 rates in the 28.6-to-29.1-GHz band. The 120 kg satellite was placed in a 580 km × 535 km orbit at 97.7° inclination.[6] References1. ^In the Matter of Teledesic Corporation: Application for Authority to Construct, Launch, and Operate a Low Earth Orbit Satellite System in the Domestic and International Fixed Satellite Service. File Nos. 22-DSS-P/LA-94, 43-SAT-AMEND-95, 127 SAT-AMEND-95. Federal Communications Commission, March 14, 1997. (Initial Teledesic FCC authorization.) Accessed March 15, 2010. 2. ^In the Matter of Teledesic LLC Application for Authority to Construct, Launch, and Operate a Ka-band Satellite System in the Fixed-Satellite Service. File Nos. 22-DSS-P/LA-94, 43-SAT-AMEND-95, 127 SAT-AMEND-95, 195-SAT-ML-97. Federal Communications Commission, January 31, 2001. (Teledesic FCC Modification.) Accessed March 15, 2010. 3. ^de Selding, Peter B. "Teledesic Plays Its Last Card, Leaves the Game". Space News, July 14, 2003. Accessed March 15, 2010, via the Internet Archive. 4. ^{{cite book |last1=Khan |first1=Riz |title=Alwaleed, Businessman Billionaire Prince |date=2005 |publisher=HarperCollins |location=New York |isbn=9780060850302 |page=135}} 5. ^{{cite web |url=http://space.skyrocket.de/doc_sdat/batsat_t1.htm |title=BATSAT (Teledesic T1) |last1= Krebs |first1=Gunter Dirk |date=4 March 2011 |publisher=Gunter's Space Page |accessdate=17 April 2011}} 6. ^{{cite journal |date=1 March 1998 |journal=SPACEWARN Bulletin |issue=532 |publisher=NASA's National Space Science Data Center/World Data Center |url=http://nssdc.gsfc.nasa.gov/spacewarn/spx532.html |title="SPACEWARN Bulletin Number 532" |accessdate=17 April 2011 }} External links
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