Unit 7 Section 4 Cross-curricular connection

How BDS works

What is BDS?

BDS, officially known as the BeiDou Navigation Satellite System, is one of the global navigation satellite systems.

How does BDS work?

•BDS is a group of satellites in orbit around the Earth.

•Each satellite sends radio signals to the Earth with information. The signals answer two important questions: "Where in space is the satellite?" and "When did the signal leave the satellite?"   

•The radio signal travels through space at the speed of light—that is 299,792 kilometres a second!

•Back here on Earth, your phone receives the signal and compares it to the exact time of arrival. The phone then calculates how far it is from the satellite.

•One satellite is not enough. Your phone needs information from four satellites to calculate your location. It does this all the time. So, when we use a BDS device, we won’t get lost.

What’s special about BDS?

We can also use BDS for two-way communication. In areas without any mobile network, people can send text messages through BeiDou satellites.

How do we use BDS?

If your phone supports BDS, it will automatically pick the navigation system with the best signal at the time.

Can we use BDS outside China?

Yes, we can use BDS outside China, but its accuracy is higher in China and the Asia-Pacific region.