BeiDou Navigation Satellite System logo.
July 25, 2015
Long March 3B launches dual Beidou satellites
China launched a new pair of navigation satellites in the move to advance the completion of the Phase III of its Beidou program. The launch took place at 12:29 UTC from the LC launch comple of the Xichang Satellite Launch Center, using for the first time the combination of the Long March-3B rocket with the new Expedition-1 (Yuanzheng-1) upper stage.
Beidou navigation satellite
The Beidou Phase III system includes the migration of its civil Beidou 1 or B1 signal from 1561.098 MHz to a frequency centered at 1575.42 MHz, the same as the GPS L1 and Galileo E1 civil signals.
Its transformation from a quadrature phase shift keying (QPSK) modulation to a multiplexed binary offset carrier (MBOC) modulation is similar to the future GPS L1C and Galileos E1.
Image above: Compass/Beidou constellation will consist of five geosynchronous (GEO) satellites, 27 in medium-Earth orbit (MEO), and three in highly-inclined geosynchronous orbits.
The long-term goal is to develop a global navigation satellite network similar to the GPS and GLONASS by 2020, eventually consisting a constellation of 35 vehicles, including 27 MEO (21,500 km orbits) satellites, three IGSO satellites (inclined at 55 degrees) and five GSO satellites.
For more information about China Aerospace Science and Technology Corporation (CASC), visit: http://english.spacechina.com/n16421/index.html
Images, Text, Credits: CASAC/News.CN/Wikimedia/Orbiter.ch Aerospace.