Method Of Moments In Time Domain Research Articles

ESD field penetration into a populated metallic enclosure a hybrid time-domain approach

This paper presents a method for the analysis of the electromagnetic field inside a metallic enclosure populated by printed circuit boards (PCBs) and a comparison with an analogous field into an empty box is also reported. The field source is represented by an electrostatic discharge (ESD) current flowing along a monopole and producing an electric field coupling into a shielded structure through a slot. The model is based on a time domain approach and the solution of the electromagnetic problem is achieved by a hybrid method, characterized by the combination of the method of moments in time domain (MoMTD) and finite difference in time domain (FDTD); this technique allows one to investigate the complex geometry of the problem and to evaluate the strong coupling between the source and the victim structure. All simulated results are validated by measurements.

Numerical verification of time-domain moment method in ultrasound tomography

In ultrasound tomography the time-domain moment method is very promising in that it has been shown to yield a close agreement between the time-spatial moment expansion and the true field representation. This paper introduces a numerical technique to compute the analytical solution for forward scattering by using a Bessel function series and the inverse discrete Fourier transform, and shows that the artifacts that occur are due to convolution aliasing and undersampling aliasing. Computer simulation has reconstructed these two types of aliasing separately, and has shown that they can be removed by a properly designed algorithm. This alias-free numerical solution is used to verify Cavicchi’s moment-method formulation. A significant improvement in numerical verification is then obtained.

Short pulse response of a circular loop

High-frequency responses of circular ring antennas and scattering structures are presented. The responses were calculated numerically by a time-domain moment method. The low-frequency inductance of a circular ring can be found by using the steady-state current resulting from an applied voltage with a nonzero dc level