基于脉内LFM-Costas频率步进的抗间歇采样干扰方法

Anti-intermittent sampling jamming method based on intra-pulse LFM-Costas frequency stepping

线性调频(linear frequency modulation,LFM)分段脉压对抗间歇采样干扰时,子脉冲顺序步进,使得采样子脉冲与相邻子脉冲脉压后,残余信号积累从而形成干扰带;干扰抑制时信号不连续采样,产生谐波分量。针对这两个问题,提出一种基于脉内Costas频率步进的LFM波形抗间歇采样干扰方法。该波形综合LFM和Costas编码的优点,具有理想图钉型的模糊函数,不仅可以抑制干扰带,还可以大大降低谐波分量,最终提高抗干扰性能。理论推导和仿真分析验证了该方法的有效性。

When linear frequency modulation (LFM) segmented pulse compression used to oppose the intermittent sampling jamming, the sub-pulses are sequentially stepped. After the sampling sub-pulses and the adjacent sub-pulses compress, the residual signals accumulate to form an interference band. When suppressing and interfering signals to sample continuously, harmonic components are produced. Aiming at these two problems, an anti-intermittent sampling method based on intra-pulse Costas frequency stepping LFM waveform is proposed. The waveform combines the advantages of LFM and Costas-coding, has an ideal ambiguity function of pin type. It can not only suppress the interference band, but also greatly reduce the harmonic components, ultimately improve the anti-jamming performance. The validity of the method is verified by theoretical deduction and simulation analysis.