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In this letter, a Quasi‐Helmholtz Projector method including multibranch Rao‐Wilton‐Glisson (MB‐RWG) basis function to calculate the scattering problem of multiscale targets at low frequencies is proposed. The loop basis function and the star basis function including MB‐RWG basis function are constructed, and the loop basis function and the star basis function including MB‐RWG basis function are used to construct the Quasi‐Helmholtz Projector. The proposed method is coined MB‐Quasi‐Helmholtz Projector (MB‐QHP) method. The MB‐QHP method can effectively solve the low frequency breakdown (LFB) problem in electric field integral equation (EFIE). Compared with the MB‐loop‐star method, the condition number is lower, the convergence is faster, and the search for global loop is avoided. Meanwhile, due to the existence of the MB‐RWG basis function, the proposed method can divide the calculation region into several regions with different mesh sizes. Numerical example shows the advantages of the proposed method.In this letter, a Quasi‐Helmholtz Projector method is proposed including multibranch Rao‐Wilton‐Glisson (MB‐RWG) basis function to calculate the scattering problem of multiscale targets at low frequencies. [ABSTRACT FROM AUTHOR]

Here, the multibranch linear–linear basis function (MB‐LL) is applied to the Poggio–Miller–Chang–Harrington–Wu–Tsai equation for calculating the scattering problem of multi‐scale dielectric targets. The MB‐LL basis function replaces the positive and negative triangles of the traditional linear–linear basis function (LL) with multiple branches, so it can be used at the junction of the meshes of different size. By using the MB‐LL basis function, we can easily divide the calculation region into several non‐overlapping regions, which is very suitable for the simulation of multiscale targets. At the same time, the MB‐LL basis function inherits the properties of the LL basis function, which is more accurate than the multibranch Rao–Wilton–Glisson (MB‐RWG) basis function. Numerical examples demonstrate the advantages of the proposed method. [ABSTRACT FROM AUTHOR]

Investigation on time- and frequency-domain responses of some complex composite structures in the presence of high-power electromagnetic pulses (EMP) is carried out in this paper. An efficient hybrid numerical method is proposed and implemented for studying an EMP penetrating through arbitrary apertures on a perfectly conducting (PEC) screen, coupled with conical spiral wire and even with Yagi-Uda antennas. This method effectively combines the time-domain integral equation (TDIE) with time-domain physical optics (TDPO), where hybrid TDIE–TDPO equations are solved by marching-on-in-time scheme (MOT). In its implementation, the antennas, wire–surface junctions, and the small part of the solid platform in the vicinity of the junctions are assigned to the TDIE region; nevertheless, a small part of the PEC screen in the vicinity of the apertures is set to be the TDIE region, while the remainder of the solid platform and the PEC screen is in the TDPO one. Our developed numerical algorithm is sufficiently verified in both time and frequency domains for predicting input admittance, S11 and S21 parameters, directivities, excited transient current responses as well as backward scattered fields of different antennas mounted on a PEC platform. These results are useful for further evaluating electromagnetic environments of some complex communication. [ABSTRACT FROM AUTHOR]