A novel extended Kalman filter (EKF) aided by precision inertial navigation system (PINS) velocity information is proposed for the application of terminal seeker random measurement error suppression.Missile motion was modeled by PINS velocity solution

while target maneuver by first-order Markov process.The dynamic model describing missile-to-target motion using the relative state vector was given

seeker random measurement error was then suppressed by using the novel EKF.The proposed filter could overcome the shortcoming of conventional filter in relative motion modeling

in which the factor of missile guidance and control might be involved.The validity of proposed filter in missile terminal guidance was then tested by simulation.