Abstract:Base on the inertial-navigation system, this article provides a method which can assist in removing the background disturbances for the infrared-guidance missiles by extracting the kinetic characteristics of targets. By the inertial-navigation information, this method firstly gets the position of the sea-sky line and narrows down the area of inferring targets, then calculates the sight angular velocity and compares it with the infrared information to distinguish the targets. The simulation tests find that during the flight process of the missile, the target moves from the sky-background to the sea-background quickly and the differences of sight-angular-velocities between target and disturbances are distinguishable for the missile seeker, which shows that the method is applicable. This method solves the problems such as the indistinct differences between targets and disturbances, a large amount of computation and instabilities under environmental changes, which arise frequently in the traditional methods which only rely on the infrared information.