为揭示太赫兹频段雷达目标散射特性,基于高频电磁计算数据研究了太赫兹雷达高分辨成像方法.考虑到传统三维雷达成像面临的大数据量问题,提出了一种成像结果类光学图像的高分辨成像方法——方位/俯仰成像方法,通过推导其点扩展函数分析了该方法在高分辨率与散射点识别方面的优势.基于电磁计算数据的仿真与分析表,高频计算方法可以快速准确计算太赫兹频段理想导体目标RCS,高分辨成像结果可以分辨目标亚波长量级的细微结构特征.因此太赫兹雷达成像技术可获取目标更加丰富和精细的信息,为目标识别带来益处。
In order to reveal the scattering characteristics of targets at terahertz frequencies,high resolution radar imaging was studied based on the high frequency (HF) electromagnetic calculation data.Considering huge data flow of 3D image formation,a novel azimuth-elevation imaging theory with its result similar to a photograph of targets was proposed.The point spread function is derived for revealing the high resolution performance and scatterers identification capability.Simulation results demonstrated that HF method can solve radar cross section of perfectly electrical conducting (PEC) target accurately and fast at terahertz frequencies.The high resolution images show that the sub-wavelength features of targets are resolvable.It also implies that terahertz radar can attain more fine information about targets,which will be helpful for target recognition.