The novel patch element shapes with the interdigital and multi-via structures for mushroom-type metasurface reflectors are proposed for controlling the reflection phases. The interdigital structure provides a wide reflection phase range by changing the depth of the interdigital fingers. In addition, the multi-via structure provides the higher positive reflection phases such as near +180°. The sufficient reflection phase range of 360° and the low polarization dependent properties could be confirmed by the electromagnetic field simulation. The metasurface reflector for the normal incident plane wave was designed. The desired reflection angles and sharp far field patterns of the reflected beams could be confirmed in the simulation results. The prototype reflectors for the experiments should be designed in the same way as the primary reflector design of the reflector antenna. Specifically, the reflector design method based on the ray tracing method using the incident wave phase was proposed for the prototype. The experimental radiation pattern for the reflector antenna composed of the transmitting antenna (TX) and the prototype metasurface reflector was similar to the simulated radiation pattern. The effectiveness of the proposed structures and their design methods could be confirmed by these simulation and experiment results.

In this paper, the author performed an electromagnetic field simulation of a typical bonding wire structure that connects a chip and a package, and evaluated the signal transmission characteristics (S-parameters). In addition, the inductance per unit length was extracted by comparing with the equivalent circuit of the distributed constant line. It turns out that the distributed constant line model is not sufficient because there are frequencies where chip-package resonance occurs. Below the resonance frequency, the conventional low-frequency approximation model was effective, and it was found that the inductance was about 1nH/mm.

We propose the architecture of efficiently and flexibly extensible solver system for electromagnetic wave simulations, that can load multi kinds of schemes such as Finite-Difference Time-Domain (FDTD) scheme, Finite Element Method (FEM), and a circuit simulator, with various boundary conditions in the system. Object-oriented approach is a promising method for efficient development of the flexible simulator. The primary object in the architecture is found through our object-oriented analysis as decomposed "region" from whole the simulation space. The decomposed region is considered to be the stage on which the electromagnetic fields play under the local rules. Developers who will extend the functionality of the system can add new classes inherited from the abstract classes in our design depending on the grid structure, the scheme, or the boundary processing method.