A high range resolution algorithm for terahertz FMCW radar imaging

The terahertz frequency modulation continuous wave (THz FMCW) imaging technology has been widely used in nondestructive testing (NDT) applications of non-metallic materials. However, due to the limited bandwidth of FMCW radar, which cannot meet the high-resolution detection requirements. In this paper, a 220–330 GHz FMCW radar and quasi-optical system are proposed. Moreover, a modified extended Fourier analysis algorithm based on continuous wavelet transform is proposed, which improves the radar range resolution from 2.9 mm to 0.8 mm. The effectiveness and advantages of the proposed algorithm are verified by artificially constructing composite materials.