Brief Introduction to the Four Major Satellite Navigation Systems

[SawyerDella]

Here is an introduction to the four major satellite navigation systems: 1. United States: GPS System: The GPS system was developed by the U.S. government in the 1970s and was fully completed in 1994. Currently, the U.S. GPS satellite positioning system is fully operational, with a total of 31 satellites in orbit, covering 98% of the Earth's surface. The GPS system provides navigation and time calibration services to 95% of users worldwide. 2. India: IRNSS System: The Indian Regional Navigation Satellite System (IRNSS) consists of 7 satellites and is expected to be operational by 2014. Currently, the IRNSS is in the debugging phase. 3. European Union: Galileo System: The Galileo system will officially become operational in 2014. Once in service, it will provide highly accurate positioning and navigation services with a precision of 1 meter for road, rail, air, and maritime transport within EU member states, as well as for hikers. Currently, only one of the two test satellites in the Galileo system is operational. 4. China: BeiDou System In December 2011, China launched the BeiDou/Compass system as a pilot project. According to Ran Chengqi, Director of the China Satellite Navigation System Office, BeiDou can currently provide navigation and positioning services for China and its neighboring countries. Ran Chengqi stated: "China's system can not only display the accurate location of users but also determine the time, and users can send text messages." Currently, the 10 satellites of the BeiDou navigation system cover an area from Australia in the south to Russia in the north, and from China's Xinjiang Uygur Autonomous Region in the west to the Pacific region in the east. In 2013, China plans to launch 6 more satellites to expand coverage, and by 2020, the system will have a total of 35 satellites. Currently, the BeiDou navigation system has an accuracy within 25 meters, which will improve to 10 meters next year. The BeiDou system will contribute to the development of China's navigation industry.