Translation Compensation and Resolution of Multi-ballistic Targets in Midcourse

Time-frequency image of multi-ballistic targets is composed of micro-Doppler of multi-targets with multi-scattering centers, which makes the methods for single target invalid. Firstly, micro-Doppler of precessing missile and swinging decoy is analyzed. Considering midcourse ballistic targets characteristics that the motion is stable and the acceleration is approximately a constant in short time, Radon transform is applied to the detection of linear degree of the micro-Doppler, then motional parameters are estimated based on minimum entropy criteria and Gauss fitting. After compensating translation, Viterbi algorithm is used to extract micro-Doppler from the time-frequency image, with which multi-targets can be resolved according to the principle that scattering centers on one target are with the same micro-Doppler cycles, but those on different targets are not. Finally, Simulations verify the effectiveness of the proposed method.