With the demand for larger bandwidths and faster data speeds, wireless communication systems are expanding into the millimeter wave and terahertz region of the electromagnetic spectrum. Successful transition to higher frequencies, particularly for systems located in urban or indoor environments, will require a thorough understanding of the reflection, transmission, absorption, and scattering of a wide variety of materials. For this study, the co-polarization and crosspolarization backscattering coefficients of several dielectrics were measured in compact radar ranges operating from 160 GHz to 1.55 THz. These structures consisted of dielectric disks with various rough surfaces. The backscattering measurements of these disks were compared as a function of polarization, incident angle, roughness, and frequency.
Successful development of remote sensing and communication systems in the terahertz band requires a better understanding of the scattering behavior of various structures. Materials that could be considered homogeneous and smooth at microwave frequencies may begin to display surface and volumetric scattering behavior in the terahertz band. The co-polarization backscattering coefficient of several types of metal and dielectric structures were measured in indoor compact radar ranges operating at 100 GHz, 160 GHz, 240 GHz, and 1.55 THz. These structures consisted of roughened aluminum plates, as well as homogeneous and inhomogeneous dielectric surfaces. The roughness and inclusions of the measured samples were tailored in order to systematically investigate various scattering effects. Polarimetric backscattering measurements of these materials were collected at elevation angles from 5 to 75 degrees. Analysis of the backscatter data supports a better understanding of surface and volumetric scattering behavior of materials at terahertz frequencies.
As terrestrial remote sensing and communication systems continue to evolve in the 0.1 – 0.3 THz band, the need to understand the scattering behavior of common materials and ground terrain at these frequencies becomes important. Terrain features and surface roughness that would otherwise appear smooth at longer wavelengths begin to significantly impact the radar cross section of the surfaces at these higher frequencies. The HH and VV polarized backscattering coefficient of several types of ground terrain and building materials were measured in indoor compact radar ranges operating at 100 GHz and 240 GHz. Measurements of the various materials were collected at elevation angles ranging from 5 to 35 degrees. The goal of the effort was to develop a better understanding of the polarimetric scattering behavior of materials in the 0.1–0.3 THz region.