Patent attributes
A method and apparatus for determining and tracking the geodetic position of a mobile platform (i.e., aircraft). The apparatus comprises a ground controller assigned to a geographic space (i.e., an airspace) and at least one mobile platform (i.e., aircraft) communicating with the ground controller on a bi-directional communications link, wherein each mobile platform (i.e., aircraft) transmits a mobile platform (i.e., an aircraft) signal comprising at least a time of transmission of the mobile platform (i.e., aircraft) signal; the ground controller transmits a ground signal comprising at least a time of transmission of the ground signal and a location of the ground controller; each mobile platform (i.e., aircraft) performs time-of-arrival (TOA) measurements on the mobile platform (i.e., aircraft) signals received by that mobile platform (i.e., aircraft) and also performs TOA measurements on the ground signal received by that mobile platform (i.e., aircraft); the ground controller performs TOA measurements on each of the mobile platform (i.e., aircraft) signals received by the ground controller; each mobile platform (i.e., aircraft) determines a range (i.e., an air range) between that mobile platform (i.e., aircraft) and other mobile platforms (i.e., aircraft) and a ground range between that mobile platform (i.e., aircraft) and the ground controller; each mobile platform (i.e., aircraft) determines its geodetic position based on at least the ranges (i.e., air ranges) and ground range for that mobile platform (i.e., aircraft) and the position of the ground controller.
