Subsurface sensing at sub-terahertz and terahertz frequencies

Development of millimeter and sub-millimeter wavelengths technologies is of great interest lately, especially for application in terahertz imaging due to bringing high resolution. In our paper we consider a tomography approach for obtaining 3-D imaging in frequency range from 100 GHz up to 325 GHz. We applied the method which we developed earlier for low frequency sub-surface tomography, for extremely high frequencies. The considered method may be used for 3D imaging in non-destructive testing. In the paper we present a theoretical model, experimental method and the comparison of results obtained at terahertz and sub-terahertz frequencies.