In today's rapid development of technology, satellite navigation systems have become an indispensable part of our lives. Whether it's city congestion or roaming in the countryside, navigation software on smartphones can always guide us to find our way. Behind this, it is inseparable from accurate satellite positioning technology.
However, an attentive person may notice a significant difference in the number of satellites between China's Beidou and United States' GPS. Why does Beidou need 55 satellites for networking, while GPS only needs 24? Are we not advanced enough?
To understand this difference, we must first start with the orbit of the satellite. Although space is vast and boundless, the orbit of a satellite is not arbitrary. It's not like you can place it however you want. It's like a road on Earth, and although the Earth's surface is vast, vehicles still have to follow a specific route.
The same is true for satellite orbits, and there is an important principle: first come, first served. Otherwise, it will be a mess, and if anyone rushes to get the way, it will lead to a satellite collision accident, and if it is not done well, it will also lead to international disputes.
As a pioneer of the global positioning system, United States GPS system has been put into use as early as the 60s of the last century. This means that the United States has absolute priority when choosing satellite orbits. After all, no one robbed him, and he was free to choose. To this end, the United States occupies orbits close to the Earth, which have short circumferences and only need to launch 24 satellites to achieve global coverage and precise positioning.
China's Beidou system started late and developed late, and it will be completed and opened in 2020. There are few advantages when it comes to choosing tracks. Before us, in addition to United States, Russia and the European Union have launched many satellites, so the low earth orbit has been fully occupied, and Beidou has to choose a higher and longer orbit.
With the increased orbital circumference and farther away from Earth, more satellites will need to be launched to maintain global coverage with the same accuracy. Therefore, the Beidou system eventually consists of 55 satellites.
In addition, there are also differences between Beidou and GPS in satellite layout. The layout of GPS is relatively simple, with 6 orbits and 4 dynamic satellites each. The Beidou satellite, which includes 30 moving satellites and 25 stationary satellites, adds complexity, but also brings higher anti-interference, reliability and positioning accuracy to Beidou.
At the same time, it leaves room for future upgrades and expansions. Another advantage is that if one of the satellites fails, it can be replaced by another one, which is very flexible.
It can be seen that the difference between Beidou and GPS in the number of satellites is not a reflection of the technical level, but the result of a combination of factors such as history, orbit selection and satellite layout. With the continuous upgrading and improvement of the Beidou system, we have reason to believe that the product of this new era will show stronger strength and broader application prospects in the future.
Sure enough, only a few years after its launch, 137 countries have now chosen to use the Beidou system, which is enough to prove its international influence and advanced performance.
In addition to the military, it is involved in all aspects in the civilian field, such as transportation, meteorological forecasting, communications, disaster relief, e-commerce and so on. Many people may not have noticed that many of our mobile phone navigation has actually changed from GPS to Beidou. In 2023, China will launch its 57th and 58th navigation satellites, which will be connected to the Beidou system after being tested in orbit. In the future, more satellites will be launched to provide Beidou service performance.