Harmonic timing sequence detection anti-jamming method and its implementation for FM fuze

In order to improve the anti-amplitude-modulation (AM)-jamming, anti-frequency-modulation (FM)-jamming and anti-sweep-jamming performance of FM fuze, a harmonic timing sequence detection anti-jamming method is proposed using the timing sequence characteristics of harmonics during the projectile-target encounter. A harmonic extraction method based on fast Fourier transform (FFT) is designed, and the harmonic amplitude is obtained by FFT on the difference frequency signal. Compared with the harmonic extraction method through the band-pass filter (BPF) of the existing FM harmonic fuze, the harmonic number and harmonic channel can be flexibly selected, under the condition of the same ranging precision. The better anti-jamming performance and flexible ignition height are achieved using the harmonic timing sequence detection. Simulation and experimental results verify the feasibility of the program and the anti-jamming success rate of FM fuze is improved from 16.7% to more than 90%.