The United States claims that China’s Beidou navigation system is far less accurate and anti-jamming than GPS.

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    Data map: China’s "Beidou" navigation satellite







    Data map: US GPS satellite


    The US GPS system is a satellite navigation and positioning system widely used around the world. At present, Russia’s "Glonass" system, Europe’s "Galileo" system and China’s "Beidou" system can enter the field of competition with GPS systems. However, on the 13th, the US Global Strategy Network published an article claiming that although countries are competing fiercely around the global satellite positioning and navigation system, the US GPS system still dominates, and other countries’ systems have many problems.


    There’s a global recognition of what GPS can do.


    The GPS system is a new generation of satellite navigation and positioning system developed by the United States since the 1970s. It took 20 years and cost $20 billion. It was fully completed in 1994. It has the ability to perform all-round real-time three-dimensional navigation and positioning at sea, land and air. The current GPS system consists of 24 working satellites and 4 spare satellites, which are distributed in 6 equally spaced orbital planes, with 4 working satellites on each orbital surface, and the satellite orbit is nearly circular. These satellites form a network with ground support systems to broadcast their position information to the world.


    The GPS system was first used in combat in the Gulf War before it was fully completed in 1991, and it achieved good results. Subsequently, it played a big role in the Kosovo War, the Afghanistan War and the Iraq War. For example, the US B-2 strategic bomber itself adopted the Global Position System for navigation and positioning. After the 16 guided bombs it carried were changed from laser guidance to Global Position System guidance, the aircraft was capable of precision strikes at night and all-weather. With the maturity of the GPS system, its use has also expanded from military to civilian fields, and the market space has expanded rapidly.


    The current GPS system provides two kinds of positioning signals, one is the so-called P code, which is encrypted and played for military use, with a positioning accuracy of less than 3 meters; the other is the C/A code, which is interfered by the standard positioning signal, with a positioning accuracy of about 100 meters, for civilian users. This code can be filtered out using the base station differential technology to achieve an accuracy of about 10 meters.


    The United States believes that other countries’ systems are not competitive


    Global Strategy Network believes that although Russia, the European Union and China are vigorously developing their own global navigation and positioning system, hoping to compete with the GPS system, but at present, these three systems still have many defects, it is difficult to compete with the GPS of the United States.


    Russia has been promoting the "GLONASS" system against the US GPS since 1976 during the Soviet era, and once reached a peak of 24 satellites in operation in 1995. But the end of the Cold War cut off the financial chain for developing and maintaining the system. By the end of 2002, the "GLONASS" system had only seven satellites in orbit. Since then, Putin’s government has stepped up the construction of the "GLONASS" system and launched a series of newly developed and more powerful satellites. By the end of 2007, the system had 18 satellites in orbit. In 2008, Russia plans to launch eight more satellites into the sky to replace the old satellites, which will restore the "GLONASS" system to "health". However, the Global Strategy Network believes that it must be seen that almost all the funds for the construction of the "GLONASS" system come from the Russian government. The current era of high oil prices has injected impetus into Russia’s economic development, so that it has sufficient funds to develop the Global Navigation and Positioning System. Maintaining the system in the future will also require a large amount of money, which will be a heavy pressure on the Russian government and will directly affect the reliability of the Russian-made system.


    Galileo is the world’s first civilian-based global satellite navigation and positioning system. In March 2002, European Union countries agreed to spend $2.70 billion to complete the deployment of the "Galileo" satellite navigation and positioning system in 2007, and plan to be completed and put into operation in 2008. Six years after the launch of the plan, some institutional problems in the European Union itself have slowed the progress of the whole plan, according to the Global Strategy Network. The "Galileo" plan is in trouble because the major European companies that won the bidding cannot agree on the cost and division of labor. So far, only one test satellite has been launched, and the second satellite will be launched this month. Its operation time has also been delayed until 2014. Arguably, current technical hurdles and financial difficulties stand in the way of Europe’s "Galileo" project, which is expected to cost $11 billion when completed, several times more than originally planned.


    The network also said that China’s Beidou system has launched four satellites, covering only East Asia, focusing on China’s coastal areas. It cannot cover the whole of China, let alone the polar regions. At the same time, the "Beidou" system has poor positioning accuracy near the equator, and the number of users is limited. In addition, the network also believes that the system’s anti-jamming ability is weak and the reliability is far inferior to the GPS system.


    Other countries’ strength is not so bad


    Although the Global Strategic Network has detailed the various shortcomings of other countries’ global navigation and positioning systems, in fact, once these systems are successfully built, they will have characteristics that GPS systems cannot match.


    Some experts in the European Union say the Galileo system has advantages in many ways. For example, its number of satellites is as high as 30, and the coverage area will be twice that of the US GPS system. In addition, the orbital position of the "Galileo" satellite is higher than that of the US GPS; the maximum accuracy of the three signals it provides is 10 times that of the US GPS, and the error range of determining objects will be within 1 meter, which is better than the error of the US GPS system of 10 meters, and can provide real-time positioning information. Many experts have figuratively said that if GPS can only find streets, "Galileo" can find garage doors. Some experts say that although the positioning accuracy of Russia’s "GLONASS" satellite positioning system is slightly lower than that of the GPS system and the "Galileo" system, its anti-jamming ability is the strongest.


Editor in charge: Li Xiuwei