https://www.flightglobal.com/a-satnav-world/30015.article
The early years of the 21st century will see the start of advanced satellite navigation systems mapping the world.
world newsflight globalsatnav
https://www.flightglobal.com/universal-dual-system-satnav-nears-approval/1083.article
Universal Avionics is on track to win certification of the first satellite-navigation (satnav) receiver capable of using both the US global-positioning system...
dual systemflight globaluniversalsatnavapproval