Cyclical modulation feature extraction of flying target based on complex AR frequency range bi-spectrum slice

Because of influences of inherent performance, automatic classification and recognition of flying target by the convention air defense radar is very difficulty in the target identification research area. Owing to the airplane revolving part can make the radar electromagnetic wave produce the cyclical modulation feature, the convention air defense radar selecting the cyclical modulation feature is quite effective in distinguishing the airplane. Complex AR frequency range bi-spectrum slice is proposed to obtain the cyclical modulation feature of helicopter, the propeller-driven aircraft and the turbofan jet airplane echo under different SNR in this paper. It solves the problem of high error of evaluation and low resolution when using traditional time-frequency analysis. Simulation results show that the error under different SNR is less than 6% using the method proposed. Both stability and distinguish ability can be got in this paper.