Communication architecture for GPS III

GPS III is a large step up from the current and modernized system, as it will provide a more sophisticated, modernized spacecraft and ground station than GPS II - GPS II having been built with 1970's and 1980's space technology. Technology upgrades, such as onboard processing and automated constellation management space-and-ground software are planned to control and maintain GPS El. This implies that the GPS III communication architecture will be quite sophisticated - with an additional driver of increased capacity for improved communications. This new sophistication is being provided to bring enhancements for both the military and civilian user. This paper summarizes three on-going studies conducted by the Aerospace Corporation in: crosslink spectrum efficiency and interference; tracking, telemetry, and control (TT&C) communication architecture; and crosslink networking analysis.