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Success in XTAR's first trials of X-band system XTAR NEWS RELEASE Posted: May 9, 2005 XTAR, LLC today announced that it has successfully completed its first field trials of the XTAR-EUR satellite for the U.S. Army's 7th Signal Brigade, based at the Army's Sullivan Barracks in Mannheim, Germany. Results of the demonstration have dramatically illustrated the capabilities of XTAR, with throughput reaching an astounding 105 Mbps, more than 12 times current capabilities. "XTAR's recent demonstrations in Germany have shown that the performance of the XTAR-EUR satellite far exceeds the current military DSCS (defense satellite communications system) satellites," said Denis Curtin, chief operating officer, XTAR. "Using a combination of high-power transponders aboard the XTAR-EUR and a few minor upgrades to the terminals, the trials were able to reach a data rate that eclipses anything that legacy systems are capable of transmitting." The XTAR demonstration used a current military tactical ground AN/TSC-85C satellite communications terminal, interfaced with a standard 16-foot U.S. Army Lightweight High-Gain X-band Antenna (LHGXA) and an 8-foot tactical satellite antenna and related system components. Minor upgrades were installed on these terminals, including a new modem by Advantech AMT, Phoenix, Ariz. and Dorval, Quebec. Also, Harris Corporation, Melbourne, Fla., and L3 Communications Systems-West, Salt Lake City, Utah, provided modified antenna feeds that allowed the 25-year old terminal to use both the left and right hand polarizations available on the XTAR-EUR satellite. Despite the age of the terminals, engineers were able to transmit the high data rates reliably over the XTAR-EUR satellite using just 40 MHz of bandwidth at 16 QAM (quadrature amplitude modulation) modulation and Reed-Solomon FEC (forward error correction) coding. Testing over the XTAR-EUR satellite's spot beam antenna achieved a user data rate of 105 Mbps on the 16-foot dish using the Harris modified antenna feed and 75 Mbps on the 8-foot dish using the L3 modified antenna feed. All testing above 8.448 Mbps was accomplished using the new Advantech modem, which has been selected by L3 for the U.S. Army's next generation Phoenix satellite terminals. Built by Space Systems/Loral (SS/L), XTAR-EUR was launched in February 2005 aboard an Ariane 5 ECA rocket. Located at 29 degrees East longitude, the satellite carries twelve 72 MHz, high-power X-band transponders that provide coverage from Eastern Brazil and the Atlantic Ocean, across all of Europe, Africa and the Middle East to as far east as Singapore. XTAR-EUR is expected to provide service for nearly 20 years. The XTAR-EUR satellite features traditional global beams as well as on-board switching and multiple steerable beams, allowing users access to X-band capacity as they travel anywhere within the footprint of the satellite. XTAR-EUR is designed to work with existing X-band terminals, as well as next generation X-band terminals that feature antennas smaller than 2.4 meters. XTAR, LLC is a new satellite communications company committed to serving the long-haul communications, logistics and infrastructure requirements of the U.S., Spanish and allied governments. The company is a joint venture between Loral Space & Communications, which owns 56 percent, and HISDESAT, which owns 44 percent. XTAR is headquartered in Rockville, Md., and has offices in Arlington, Va., Palo Alto, Calif. and Madrid, Spain. HISDESAT Servicios Estrategicos S.A. is a Spanish company headquartered in Madrid. HISDESAT's aims are the acquisition, operation and commercialization of Government-oriented space systems, beginning with satellite communications in the X- and Ka-band frequencies. HISDESAT is owned jointly by HISPASAT, S.A., the Spanish commercial satellite services company, INSA and the leaders of Spain's space industries: EADS-CASA Espacio, INDRA and SENER. HISDESAT will provide enhanced capabilities, including Ka-band, for Spain's defense applications. Loral Space & Communications is a satellite communications company. Its Space Systems/Loral division is a world-class leader in the design and manufacture of satellites and satellite systems for commercial and government applications including direct-to-home television, broadband communications, wireless telephony, weather monitoring and air traffic management. Through its Loral Skynet division, it owns and operates a fleet of telecommunications satellites used to broadcast video entertainment programming, distribute broadband data, and provide access to Internet services and other value-added communications services. |
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