Patent attributes
A system to provide navigation solutions for vehicle landing guidance comprises onboard aiding sensors, an IMU, a radar altimeter, a map database, and a navigation system including a navigation filter that outputs estimated kinematic state statistics for the vehicle. An onboard processor inputs horizontal and vertical position statistics from the navigation filter into the map database, and computes an estimated ground/object height, ground/object velocity, ground/object acceleration, and error statistics thereof, based on terrain and object map data. The processer includes a radar altimeter inertial vertical loop (RIVL) filter that determines relative vertical acceleration based on a difference between vehicle vertical acceleration and ground/object vertical acceleration; determines relative vertical velocity based on a difference between vehicle vertical velocity and ground/object vertical velocity; performs consistency checks on the relative vertical acceleration and relative vertical velocity; and outputs estimated vehicle vertical position and vertical velocity statistics for compensation of the navigation filter outputs.
