Analysis Of Doppler Features Of Maneuvering Reentry Missile With Time-frequency Transform

The work of this dissertation is focused on research of Doppler features of maneuver of reentry missile with time-frequency transform.To have excellent penetration capability, the ballistic missile periodically maneuvers during the process of reentry, such as spiral maneuver, swing maneuver, snake-wriggling maneuver. The defenses against ballistic missile usually make use of hit-to-kill interceptor which flies along the inverse orbit of the target missile. So it's very necessary to study the reentry maneuvers of the target ballistic missile. Firstly this dissertation introduces relational concept, mode of operation, reentry maneuvers of ballistic missile and the movement of the body itself accompanying with the trajectory movement. The echo signal of maneuvering target is non-stationary, which should be analyzed in the joint time-frequency domain by applying time-frequency transforms. Then the mathematical model of spiral maneuver of reentry missile is proposed in this paper and the time-varying Doppler feature is studied in the time-frequency domain, which can provide useful information for target recognition, detection, tracking and interception. Finally, to provide additional information, the micro-Doppler effect of the body movement is introduced. The mathematical model of micro-Doppler effect, which is induced by the rotation of a target body, is developed. The author separately simulates the micro-Doppler frequency characteristic while the body spinning, rolling and coning.