Characterization of sub-range-bin spatial features with frequency modulated continuous wave radar operated at 650 GHz

In this paper we present imaging results obtained from frequency modulated continuous wave radar setup operated at 650 GHz and optimized for imaging of objects with lateral dimensions between 1-20 cm. We consider in particular the ability and the benefits of using such system for resolving features corresponding to depth variations smaller than the standard depth resolution of FMCW systems. This is accomplished by observing the lateral variation of the amplitude and the phase of the reflection coefficient within one range bin. The presented imaging results from 3D printed plastic phantom objects resolve features with depth profiles down to 0.1 mm in the system with a range bin of 5 mm.