Use of the perfect electric conductor boundary conditions to discretize a diffractor in FDTD/PML environment

Abstract

In this paper we present a computational electromagnetic simulation of a multiform diffractor placed at the center of an antenna array. Our approach is to solve Maxwell's differential equations with a discrete space-time formulation, using the Finite Difference Time Domain (FDTD) method. The Perfectly Matched Layers (PML) method is used as an absorbing boundary condition, to prevent further spread of the electromagnetic wave to the outside of the calculation region. The Perfect Electric Conductor (PEC) boundary conditions are used to represent the periphery of the region and the diffractor. The system consists of an antenna array of 20 elements: a transmission antenna (TX1) which feeds a Gaussian pulse with center frequency of 7.5 GHz, and 19 reception antennas (RX1 to RX19), which serve as sensors. The diffractor is discretized for integration into the environment FDTD, and two case studies are presented according to their geometric shape: square and circular diffractor. In this work, the goal is to determine the Maxwell's equations, analyze all the zones that form the diffractor and plug them in the computational algorithm in Matlab. We show the equations for each case and obtain the electromagnetic parameters of the system: electric fields, magnetic fields, and reflected power, sensed by the RX's.