Patent ID: 7221317

Claim:
In a system of navigational satellites, at least one of the navigational satellites having a wide beam antenna transmitting a first navigation signal and a spot beam antenna transmitting a second navigation signal, a method of estimating a lever arm correction between the wide beam antenna and the spot beam antenna, comprising the steps of: receiving a target position of the spot beam over the time period T in the satellite; generating a predicted position of the at least one satellite over a time period T; generating predicted satellite attitude over the time period T from a profile of a prescribed satellite maneuver over the time period T; generating predicted gimbal angles of the spot beam antenna over the time period T from the predicted satellite attitude and the target position of the spot beam over the time period T; predicting the lever arm correction between the wide beam antenna and the spot beam antenna over the time period T from the predicted gimbal angles of the spot beam antenna over the time period T and the predicted satellite attitude over the time period T; and transmitting the predicted lever arm correction from the satellite to a navigational receiver.