A Novel Multibranch Linear-Linear Basis Function for Improving the Accuracy of Multiscale PEC Scattering Analysis

A novel multibranch linear-linear (MB-LL) basis function is proposed to improve the accuracies of the magnetic field integral equation (MFIE) and the combined-field integral equation (CFIE). The MB-LL basis function inherits the merits of the conventional linear-linear basis function. By using the basis function, the positive and negative triangles can be replaced by multiple branches, thereby allowing the use of different mesh densities in each region of the simulation. Compared with the multibranch Rao–Wilton–Glisson (MB-RWG) basis function, the MB-LL basis function can be applied to effectively improve the calculation accuracies of MFIE and CFIE. Several numerical examples show that the MB-LL basis function can be used for improving the accuracies and reducing the computational consumptions. It is a robust approach for the analysis of multiscale targets.