BDS is a global navigation satellite system which is a
self-development and independent operation of China. BDS
consists of the space segment, ground segment and user
segment.
The space segment includes five satellites in geostationary
orbit and 30 non-geostationary orbit satellites. The ground
segment includes the master control station, the injection
station, the monitor station and other ground stations. The user
segment includes BDS user terminal and terminals compatible
with other terminals.
It offers all-weather and all-time positioning, navigating
and timing services on a global scale for all types of users with
high accuracy and reliability, and has capability of short
message communication. Now, the second generation BDS is
currently used