Global positioning system is our best navigation network, but this may change in five years - ABC News
50 SW completes GPS constellation expansion > Schriever Space Force Base (Archived) > Article Display
![Launch of First GPS III Satellite Begins Modernization of the GPS Constellation - Inside GNSS - Global Navigation Satellite Systems Engineering, Policy, and Design Launch of First GPS III Satellite Begins Modernization of the GPS Constellation - Inside GNSS - Global Navigation Satellite Systems Engineering, Policy, and Design](https://insidegnss-com.exactdn.com/wp-content/uploads/2018/12/Screen-Shot-2018-12-24-at-9.42.25-AM.png)
Launch of First GPS III Satellite Begins Modernization of the GPS Constellation - Inside GNSS - Global Navigation Satellite Systems Engineering, Policy, and Design
![Global Positioning System (GPS). n 24 satellite constellation u Semi-synchronous, circular orbits (~20,200 km/10,900 nautical miles altitude) u Six orbital. - ppt download Global Positioning System (GPS). n 24 satellite constellation u Semi-synchronous, circular orbits (~20,200 km/10,900 nautical miles altitude) u Six orbital. - ppt download](https://images.slideplayer.com/24/7278721/slides/slide_2.jpg)