集成时频特征的拖曳式诱饵存在性检测方法

Detection of Presence of Towed Radar Active Decoy Integrated the Time-Frequency Characteristic

拖曳式诱饵干扰为实现角度欺骗需要通过目标机动来形成导弹、目标、诱饵三角态势,弹目距离的接近以及三角几何关系的剧烈变化导致雷达接收回波中目标与诱饵的多普勒频率呈现时变非平稳特性。传统傅里叶分析方法无法反映频率分量随时间的变化情况,易导致谱线展宽和分辨力下降,使得基于频谱展宽的干扰检测具有很大的局限性。在分析诱饵干扰特点以及时频变化特性的基础上,将目标与干扰的回波分段近似为多分量线性调频模型,利用时频分析展现频率特征随时间的演变规律,采用WVD(Wigner-Ville distribution)与霍夫变换(Hough transform)相结合的方法检测接收回波中的多分量信号峰值,结合干扰特性设计阈值门限,实现了雷达波束内拖曳式诱饵干扰的存在性检测判决。末制导典型场景下的仿真实验验证了方法的有效性。

The towed radar active decoy（ TRAD） flies with the airplane to form the triangular state through the maneuver flight,and the geometry relationship among the radar,airplane and decoy changes rapidly. In the course of jamming,the Doppler frequency characteristics of the airplane and the decoy are both time varying. Traditional FFT is unavailable to display the variety of frequency along with the time,brings out the expanded spectrum and declined resolution,and that causes the method based on the expanded spectrum limited when used for jamming detection. Based on the analysis of the jamming and time frequency characteristics,the LFM model of the target echo and jamming signal are approximated for sections,the time-frequency analysis is used to exhibit the variety law of the Doppler frequency vs time,and the Wigner-Ville Distribution and Hough transform are combined and adopted to detect the peak value of the multiple signals. The threshold is designed according to the decoy features,and the detection of presence of TRAD is realized. Simulation results under terminal condition illustrate the performance of the method.