The last 3rd-generation BDS-3 satellite required to complete full worldwide cover was launched on 23 June.
Launch took place from the Xichang Satellite Launch Centre at 0943 local time (0143 UTC), having been delayed from 16 June due to problems with the Long March-3B launch rocket.
This 55th BDS satellite will use its own propulsion to obtain a geosynchronous equatorial orbit (GEO) at ~22,000 miles (~36,000 km).
The final constellation comprises 27 medium earth orbit (MEO), 5 GEO and 3 inclined geosynchronous orbit (IGSO) satellites. This should provide global navigation services similar to GPS, GLONASS and Galileo.
The worldwide BDS-3 will use, amongst other transmissions, a frequency of 1575.42 MHz - the same as GPS L1 and Galileo E1 civil signals; and it will use multiplexed binary offset carrier (MBOC) modulation, similar to the future GPS L1C and Galileo’s E1. Satellite-based augmentation (SBAS) and SAR facilities are included.