China Plans Global Satnav System

China Plans Global Satnav System

With navigation satellite constellations rapidly becoming a must-have for any major world power, China has joined Europe and Russia as an aspirant to match US sat nav technology. The People's Republic has announced that it will upgrade its localised Beidou satellite system to global coverage by 2015.



The only worldwide sat nav constellation currently in service is the American Global Positioning Service (GPS), funded by the US military. The unencrypted, free-to-use GPS civil signal is used by the vast majority of satnav kit worldwide. The former "selective availability" option, in which the accuracy of the civil GPS signal could be degraded, has now been discontinued. However, America retains the option of denying GPS service at places and times of its own choosing.