基于离散正弦调频变换的中段多微动目标分离

弹道导弹在飞行中段形成目标群，窄带雷达无法从距离上将弹道目标分离。为使窄带雷达具备分离弹道目标的能力，对弹道目标的微动特性进行研究。对振动目标的信号回波进行建模，分析其在离散正弦调频变换（DSFMT）中的聚敛特性。利用多分量信号在变换域中的聚敛特性，实现不同信号分量的分离，并估计出目标的振动频率。仿真实验表明，在信噪比-10 dB下，多个振动目标散射点的窄带雷达回波在DSFMT域上具有明显的聚敛特性，分辨出了不同的振动散射点，振动频率估计均方根误差小于-2.5 dB。 

Separation of midcourse multiple micro-motion targets based on DSFMT

The ballistic missile forms a target group in its mid-flight, and the narrowband radar cannot separate the ballistic target from the distance because of its narrow bandwidth. In order to enable narrowband radar to separate ballistic targets, the micro-motion characteristics of ballistic targets were studied. The narrowband radar signal echo of vibration target was modeled and its convergence characteristics in discrete sinusoidal frequency modulation transform (DSFMT) domain were analyzed. The convergence characteristics of multi-component signals in the transform domain were studied to separate different signal components and the vibration frequency of the target was estimated. The simulation results show that the narrowband radar echoes of multiple vibration ballistic targets have obvious convergence characteristics in the DSFMT domain under the signal to noise ratio of -10 dB, the proposed algorithm can distinguish different vibration scattering points, and the estimated vibration frequency root mean square error is less than -2.5 dB.