Sketch map of use of Chinese “Triones” Satellite Navigation System
American “Space News” reveals that Chinese “Triones” military satellite navigation system under planning disturbs American plan. Chinese spaceflight department is trying to use European “Galileo” system for reference and try to suppress the military superiority of American satellite navigation system by launching M programming signal similar with American navigation system. The best solution for America is to develop GPS-4, i.e. the forth generation of GPS system.
On midnight 34, 25, May, 2003, China successively launched the third “Triones No.1” Navigation positioning satellite to the outer space by “March No. 3 Jia” launch vehicle in XiChang satellite launch center. The previous two “Triones No.1” satellites were launched respectively on 31, October, 2000 and 21, December, 2000 and the navigation positioning system functions stable so far. The satellite launched this time is the backup satellite.Integrated with the previous two satellite, it comes a complete satellite navigation positioning system which ensures to provide 24-hour information of satellite navigation.
The launch of the third “Triones” satellite indicates that China will be the third country with complete satellite navigation system successive to American global satellite positioning system (GPS) and the former Russian global navigation positioning system (GLONASS). The establishment of the system plays a positive role in China’s civilian defense and economic construction as well.
China has started research in satellite navigation system since 1950’s, but all are broken down because of various reasons. China set about independent “Transit ” navigation system research is much later that in later use of appearance we could only depend on import. From late 1960’s on, China probe into research on the satellite navigation system, which is accustomed to Chinese state situation. Regional system plans of single-satellite, double-satellite, triple-satellite, 3-5 satellite and multi-satellite global system idea have been successively proposed and comprehensive implementation of navigation positioning and communication have been considered. However, they are not realized due to various reasons.
The GEOSTAR system, which is proposed by three American scientists in July 1982 and named in December 1982, is the initiative satellite positioning system of the said kind of double-satellite. During implementation, the research fund of GEOSTAR system has to be taken away due to the prosperity and fast development of the much more advanced GPS satellite positioning system, which results in the failure of GEOSTAR and its system. The “Triones No. 1” satellite navigation system in China is right the “double-satellite expeditious positioning system” developmental plan proposed in the 1970’s. The plan of Triones satellite navigation system was put forward in 1983. Its prominent characteristic is that the number of constructive satellites is less and that the user’s terminal device is simple, and that all complexity fastens on the central processing station on earth. “Triones No. 1” satellite navigation system is such kind of regional satellite positioning system which provides 24-hour services of expeditious positioning and brief digital information communication via earth synchronous satellite.
GPS global satellite positioning system：
GPS (Global Positioning System) is a system used in global position locating. It was an achievement of a giant aerospace project sponsored by the US government through more than 20 years at a cost of 12 billion USD. It’s a third giant aerospace project successive to Apollo Project and space shuttle plan. Its main purpose is to provide 3-D position, 3-D speed, and high precise temporal information and to radically solve the problem of navigation and positioning on earth then to satisfy the needs of different customers.
l Military use: used by army, navy and air force. The US army not only uses this technology in airplane, missile and other high-tech weapons, but also equips receive device for the individual soldiers.
l Civilian use: used in civilian plane and ship navigation, and other civilian project positioning.
l Navigation: exclusively used in mass airplane and ship navigation.
l Timing: used as timing device by various of observation station and astronomical observation station
l Geodesic measuring: used in geodesic measuring and geodynamics observation
The main part of GPS system is composed by 24 earth synchronous satellites, which together with the supporting system constitute a network to deliver its position information globally. At user’s part, the most important thing is the GPS receiver, which according to the synchronous position information from 4-8 satellites, applying positioning theory of squared differences to deliver its position (longitude), speed, height and temporal information to users every 1 to 3 second for reference by users and their system.
GPS supplies tow kinds of positioning signals, one of which is called C/A code, formed by disturbed positioning signals. The positioning precision of this kind of positioning signal is about 100 meters and is mainly used with civilian purposes. The other is called P code, delivered after encrypt, and used with military purposes. Its positioning precision is about 3 meters. As for the civilian C/A codes, the molestation can be filtrated by the ground squared difference technology to promote its precision to about 10 meters.
GPS receiver device is made up by a GPS hand phone, whose volume is equivalent to that of a cell phone. Its computer interface consists of GPS an incept clip or a USB device, and is made up by cables, receiver unit and power supply. It’s so smart that it can be equipped to cars and other engines.