Transmitted electromagnetic field through an aperture in a perfect electric conducting wall by marching-on-in-degree approach in time domain

In this paper a time-domain (TD) method-of moments (TD-MoM) technique is applied to evaluate the transient penetrated fields through a rectangular aperture in a perfect electric conductor (PEC) plate. The incident wave is assumed to be a Gaussian plane wave. Here, by using weighted Laguerre polynomials, as entire-domain temporal basis functions, the MoM based technique is modified to a technique called marching-on-in-degree (MOD) approach to calculate the electromagnetic fields at any point in front or behind the perforated wall. MOD overcomes the late-time instability problem that often occurs in the marching-on-in-time (MOT) technique. The technique is validated for a finite and also infinite PEC plate with one aperture. While the Inverse-Discrete-Fourier-transform (IDFT) results of a frequency domain solution is used to assess the proposed method for the problem of aperture in finite size conducting wall, for the infinite wall with aperture, CST results are compared to show the accuracy of the proposed MOD. In addition, the effect of apertures with different lengths on the transmitted field is demonstrated.