Method and apparatus for providing an integrated communications, navigation and surveillance satellite system

摘要

A system for providing integrated communications, navigation and surveillance capabilities. A space segment comprises a plurality of time synchronized satellites broadcasting navigation signals and have two-way communication capabilities. Each satellite also has communication switching capabilities and is part of a network. A terrestrial segment comprises processing apparatus that communicates the satellites through the network. A user segment comprises at least one mobile user device capable of two way communication with the plurality of satellites and of using the navigation signals to derive its position. The user device broadcasts surveillance signals which the processing apparatus uses to derive the position of the user device. The signals are also used by the system to measure and transmit the state of the ionosphere.