| The hybrid volume and surface integral equation approach is applied to solve electromagnetic scattering and radiation problems involving conducting and/or dielectric objects. To flexibly and accurately model the complex structures and maintain the minimum number of unknowns, mixed mesh scheme is proposed to discretize the object. Zeroth-order divergence-conforming basis functions on triangle, quadrangle, tetrahedron, hexahedron, prism and pyramid are used to model the induced current on the object.; Because of the large amount of the memory and CPU time requirement of traditional Method of Moments (MoM), which is proportional to O(N 2), Multilevel Fast Multipole Algorithm (MLFMA) is applied to reduce the operation and memory requirement to O(N log N) when solving the impedance matrix equation resulted from the integral equations by an iteration solver.; To further reduce the number of unknowns, increase the accuracy and convergence rate, higher-order divergence-conforming basis functions over the above mesh elements are introduced to model the induced current on the object.; By combination of mixed-mesh scheme, MLFMA, and higher-order basis functions, it is practical to simulate complex, large-scale EM problems. |
