SAR轮式和履带式车辆三维微多普勒建模与回波仿真研究

摘要

机载合成孔径雷达(SAR)回波数据是机载SAR信号处理的基础,然而靠飞行试验得到的实测数据价格昂贵且不灵活.针对这一问题,提出了一种可以在实验室中对机载SAR微动目标回波数据进行仿真的方法.首先,叙述了SAR运动点目标回波数据模拟的理论模型,提出了三维SAR运动点目标回波数据模拟的方法,并根据轮式和履带式车辆的结构特征与运动特征分别建立了两者的理论模型,给出了模拟实验的结果；然后,通过时频分析对不同车辆在不同速度情况下的回波信号进行了分析比较.仿真和研究结果显示:该理论建模方法正确有效,能够很好地用于在实验室中实现对机载SAR微动目标回波数据的仿真,回波信号的微多普勒特性为已有的目标识别方法提供了重要辅助条件.%Echo data of airborne synthetic aperture radar (SAR) is the foundation of airborne SAR signal processing, however the measured data from air trials is expensive and inflexible. Aiming at this problem, a method that can simulate an airborne SAR echoes data of micro moving target in the laboratory was proposed. Firstly, the theoretical model of SAR moving point target echoes data simulation was presented, and the method of 3-D SAR echoes data simulation was proposed. According to the structural characteristics and motion features of wheeled and tracked vehicles, two theoretical models were built and the results of simulation experiments were presented. Then the echo signals of different vehicles with different speeds were compared by using time-frequency analysis. The results indicate that this theoretical model is correct, and which can simulate airborne SAR echo data of micro moving target in laboratory, the micro-doppler characteristics analysis of echo data provides important supple-military conditions for existing target recognition methods.