The BeiDou Navigation System is a satellite navigation system operated and managed independently by the People's Republic of China. It has two distinct groups of satellites that has been providing a limited level of service since 2000. Its first version, officially called the BeiDou Navigation Experimental System, also known by the name BeiDou I, was operating with only three satellites and offer services primarily for Chinese customers and other nearby regions.

The system is run by the China Navigation Satellite Project Centre. The second phase of the system which has been functioning under the nomenclature of BeiDou Navigation System which is also known as COMPASS or BeiDou II, will be a global system when it is fully functional with its 35 satellites. Out of these 35 satellites, 5 will be in geostationary orbit and the remaining in medium earth orbit.

A ground-based augmentation backbone network, currently under construction, will be used to complement the orbital section of the system. Both parts will together be used to provide a real-time differential positioning sservice to China and surrounding areas, with an accuracy at a meter or smaller level.

Although the navigational system has been in operation with ten satellites serving the Chinese region since 2011, it was in the following year when it started offering services to clients in the Asia-Pacific region. Full global coverage is expected to be available in 2020.

The navigation system was named after the Big Dipper constellation, which in Chinese parlance is known as BeiDou, literally meaning “Northern Dipper”. It was named as such by Chinese astronomers in reference to the Ursa Major constellation, having seven bright stars. These stars have traditionally been used for navigation in the northern hemisphere.

According to an expert in the field of satellite navigation, one of the sectors where the BeiDou 2 system is expected to be in heavy use is transportation. Using the BeiDou system along with GPS will give users better accuracy.