连续波调频引信分数域匹配阶抗扫频干扰方法

In order to address the issue of frequency sweeping jamming that a frequency modulated continuous wave (FMCW) fuze is susceptible to, a method for suppressing the frequency sweeping jamming based on matching transform order in fractional Fourier domain is designed. This method is based on the characteristics that the target echo beat signal of FMCW fuze is superimposed by multiple single-tone signals,and the jamming beat signal is linear frequency modulation signal. The position of jamming signal is obtained using the aggregation of linear frequency modulation signals at a specific order in the fractional Fourier domain through one-dimensional constant false alarm rate(1D-CFAR) detection. This method eliminates the impact of jamming on fuze by reconstructing the amplitude and phase of signal at the interfered location. Moreover,a fast search algorithm for frequency modulation,utilizing the iterative golden section search (GSS) method, is developed for the optimization of fractional order of jamming signals. The effectiveness of the proposed method was verified through the simulated and measured data. The results indicate that the proposed method can effectively suppress the frequency sweeping jamming when the signal to interference plus noise ratio(SINR)is below-20 dB.