Patent ID: 7474962

Claim:
A method for providing relative navigation between two objects in motion, where a first object is approaching to land on a second object, the method comprising: receiving navigation information from the first object; receiving navigation information from the second object; integrating the navigation information from the first object with the navigation information from the second object to determine a stabilized relative position and velocity vector between the first and second objects; and based on a last known state of the second object, providing an estimate of the relative velocity vector and the relative position at a point forward in time for navigation purposes, wherein integrating the navigation information comprises performing the following on a processor: determining a combined GPS code based an uncorreted GPS code and carrier double differences combined with a predicted GPS code and carrier double differences and the received navigation information from the first and second objects; calculating a baseline relative position vector based on the received navigation information from the first and second objects; calculating a double difference code based on the baseline relative position vector; calculating a relative position and velocity vector based on the double difference code, the combined GPS code and the received navigation information from the first and second objects; and stabilizing the relative position and velocity vector, wherein the estimates of the stabilized relative position and velocity vector are computed by differencing absolute positions of the ship and aircraft in a first operational mode, wherein the estimates of the stabilized relative position and velocity vector are computed using a relative navigation Kalman filter based on one of double differenced single frequency or narrow lane pseudo-range (code) measurements in a second operational mode, and wherein the estimates of the stabilized relative position and velocity vector are computed using the relative navigation Kalman filter based on double differenced single frequency or narrow lane code and double differenced single frequency or wide lane carrier measurements in a third operational mode.