At 9:43 am on June 23, China successfully launched the 55th navigation satellite of the Beidou system, finishing the deployment of the navigation system constellation half a year earlier than originally planned.
After ensuring the stable and reliable operation of the system, China will provide users with all-weather and high-precision global positioning navigation and timing services as well as short message communication, precision single-point positioning and other services.
China's Beidou satellite navigation system engineering chief designer Yang Changfeng previously said the Beidou system took more than 20 years to go through the 40-year development path of navigation systems in other countries.
Over the past 20 years, China has conducted 44 Beidou launches at the Xichang Satellite Launch Centre.
Using the Long March 3-A series of launch vehicles, China has launched 4 Beidou-1 test satellites, 55 Beidou-2 and Beidou-3 test satellites and 55 Beidou-4 test satellites. The networked satellites have been sent to a predetermined orbit.
Since the start of global networking in 2017, 18 launch missions have been carried out at high density in two and a half years.
In 1983, Chen Fangyun, the pioneer of Chinese satellite measurement and control technology, proposed the idea of a "two-star positioning system".
In 1994, China officially set up a special research project on the Beidou navigation system.
In 2000, China launched two geostationary orbit (GEO) satellites, and the Beidou-1 system was completed and put into operation.
In 2004, the construction of the Compass II system was launched. By 2012, 14 satellites had been launched and networked.
In 2009, the construction of Beidou-3 system was started. By 2020, 30 satellites were launched and networked, and the Beidou-3 system was fully completed.
This is by far China's largest, most extensive coverage, highest service performance and most closely related to people's lives and is also China's first major space infrastructure to provide public services to the world.
The Beidou system, together with the U.S. Global Positioning System (GPS), the Russian Global Navigation Satellite System (GLONASS) and the European Union's The Galileo positioning system (Galileo) is recognized by the United Nations Committee on Satellite Navigation as one of the four cores of the global satellite navigation systems.
According to Guotai Junan Securities, the US currently leads the world in GPS systems, but the Beidou system is gradually catching up.
In terms of positioning accuracy, the Beidou system is within 10 meters of civil positioning accuracy globally and within 5 meters in the Asia-Pacific region. With the enhanced system, the accuracy can reach 1 meter. This is far better than the GPS global positioning accuracy of less than 10 meters.
In terms of speed and timing accuracy, Beidou-3 can also match the accuracy of GPS global timing.
