China will launch about 30 satellites by the end of 2020 for its Beidou Navigation Satellite System and will build a network of ground augmentation stations to improve its coverage and accuracy, said a senior project official.

Ran Chengqi, director of the China Satellite Navigation Office, said that when those satellites are put into service, Beidou will have global coverage.

Beidou is the fourth such system, following the United States' GPS, Russia's GLONASS and European Union's Galileo.