Reduction of the Perfectly Matched Layer Reflection Effects to Improve the FDTD Accuracy in Remote Sensing of Infinite Electromagnetic Media with Random Rough Surfaces

Simulation of unbounded media always necessitates inordinate usage of computer resources. So, using of absorbers with high absorption performance is one of the most important challenges in electromagnetic simulations of the finite difference time domain (FDTD) method. Weak absorbers can cause some reflected waves into the simulation medium and consequently non-realistic results. To improve the absorption of electromagnetic waves, this paper introduces a new approach in absorbers to provide a simultaneous use of the absorbing media with a proposed boundary equation. This approach reduces the perfect electric conductor effects at the end of the absorbing media and enhances its absorption performance. To analyze this method, we utilize a rough surface test procedure as one of the most useful problems in remote sensing. This test simulates a real media in laboratory conditions with Gaussian rough surface and point source. In addition, the relative error of the new method will be compared to the other conventional methods, and effectiveness of the proposed method will be validated.