一种新的基于相位扰动的线性调频信号SAR抗干扰方法

A New Method of Phase-perturbed LFM Chirp Signals for SAR ECCM

以数字射频存储技术(DRFM)为代表的有源相参干扰是对抗合成孔径雷达(SAR)一种行之有效的干扰方式,传统线性调频信号(LFM)合成孔径雷达对抗有源相参干扰能力较差。文中采用一种新的相位扰动线性调频信号(PPLFM),与传统 LFM 信号相比,增加了波形的复杂性,可有效提高其抗干扰能力。文中首先给出了PPLFM 信号的设计方法,重点优化了其扰动幅度矩阵;随后,分析了不同扰动参数时PPLFM信号的抗干扰性能与成像性能;最后,对其抗假目标干扰和移频干扰能力与 LFM 信号进行了比较。仿真结果表明,与传统LFM信号相比,新的PPLFM信号可以有效抑制有源相参干扰。

The active coherent jamming based on digital radio frequency memory (DRFM) is an effective method of jamming for synthetic aperture radar (SAR),and the traditional LFM signal synthetic aperture radar has poor capability of counting active coherent jamming. In this paper, a new phase-perturbed chirp signal (PPLFM) is used, which increases the complexity of the waveform compared with the traditional LFM signal and can effectively improve the ability of radar to resist active coherent jamming. First, the design method of PPLFM signal is given, and its disturbance amplitude matrix is optimized. Then the electronic counter countermeasures (ECCM) performance and imaging performance of the PPLFM signal are analyzed with different disturbance parameters. Finally, the ability to suppress false target jamming and frequency shift jamming is compared with the traditional LFM signal. Simulation results show that the PPLFM signal can effectively suppress the active coherent interference compared with the LFM signal.