FDTD modeling of a SIW based sensor for THz diagnostics

In this contribution finite-difference time-domain (FDTD) modeling and simulations of sensors for Terahertz (THz) diagnostics are described. substrate integrated waveguide (SIW) structures are addressed and their potential use as sensors is evaluated in some configurations of interest. In particular, the considered THz sensor is obtained by means of an open SIW waveguide which transmits and receives the electromagnetic waves used for the inspection of the target under test. Substrate integrated waveguides allow THz waves propagation by using quite standard Printed Circuit Board (PCB) technology and so they may be good candidates for obtaining guiding structures in the THz band with moderate costs and the possibility of integration with other devices. The adopted FDTD simulator is able to take into account of both the propagation inside the SIW and the interactions of THz waves with dielectric structures.