Low permittivity dielectric object on conductor characterization

An SAR image-based technique to obtain geometry and constitutive parameters information about low permittivity lossless dielectric materials is presented. While characterization of high permittivity dielectrics is relatively affordable in SAR images, the lower power reflected back by low permittivity objects makes their characterization a challenging task. The proposed technique combines two illumination angles (normal and 45°) for a rectangular dielectric on a strongly reflective backing to overcome the permittivity-geometry uncertainty appearing on each independent case. A simulation-based application to mm-wave portal-based system for concealed objects detection is used for validation.