太赫兹合成孔径雷达(synthetic aperture radar,SAR)带宽大,能够对运动目标高分辨成像,但目标运动导致成像移位和模糊。针对不同的运动形式,分别提出基于相位补偿和等效运动的运动目标成像方法。首先分析不同运动参数对成像的影响,然后通过补偿相位和等效载机速度获得运动目标聚焦、背景模糊的图像。通过恒虚警率(constant false alarm rate,CFAR)检测和逆成像处理获得目标和背景分别聚焦的图像。最后对两幅图像进行叠加,实现了在静止背景上对运动目标的准确成像。不同信噪比条件下的电磁计算数据仿真结果验证了所提方法的有效性。
Terahertz synthetic aperture radar (SAR) has large bandwidth and is able to acquire high resolution images of moving targets. However, the target motion leads to the position offset and obscure in imaging. Aiming to different forms of motion, the moving targets imaging method based on the phase compensation and equivalent movement is put forward. Firstly, the influence of different motion parameters on imaging is analyzed. And then the image with focused moving targets and blurred background is obtained by employing the phase compensation and equivalent load machine speed. Secondly, the images of target and background focused respectively are acquired by constant false alarm rate (CFAR) detection and inverse imaging processing. Finally, it realizes the accurate imaging of moving targets in the static background by adding the two aforementioned images together. Electromagnetic calculation data simulation results under different signal-to-noise ratio (SNR) show the effectiveness of the proposed method.