US Patent 9121940 Vehicle navigation using non-GPS LEO signals and on-board sensors

A navigation system includes a navigation radio and a sensor onboard a vehicle. The navigation radio receives and processes low earth orbit RF signals to derive range observables for a corresponding LEO satellite. A sensor is operable to generate at least one of vehicle speed data, acceleration data, angular rate data and rotational angle data under high vehicle dynamics. The navigation radio includes a navigation code operable to obtain a position, velocity and time solution (a “navigation solution”) based on the one or more range observables, ephemerides for the corresponding LEO satellite, a heading pseudomeasurement, a navigation radio altitude pseudomeasurement; one or more vehicle velocity pseudomeasurements orthogonal to the altitude pseudomeasurements; and the generated at least one of vehicle speed data, acceleration data, angular rate data and rotational angle data. The navigation radio uses the navigation solution to acquire a GPS signal during interference with a coarse acquisition GPS signal.