Space has become yet another arena for increasingly fierce international competition as many countries have developed their own navigation satellite systems. 

The U.S. GPS system is the most used navigation system. It uses 32 satellites in medium Earth Orbit and has been in operation since 1978. With 24 full orbital constellations of satellites, Russia's Global Navigation Sputnik System also offers global coverage. The EU introduced the Galileo system in 2002. In order to increase accuracy, Galileo uses a combination of its own and GPS signals. India also has its own positioning system which was put into full operation three years ago. Japan's satellite system aims to enhance the U.S. GPS in the Asia-Oceania regions, with a focus on Japan.

Join us now is Dong Lu from COMMSAT, a company providing satellite communication services in Beijing, to talk about more space activities.