Abstract
This paper proposes a new topology optimization method for the structural design of electromagnetic waveguides that perform according to specified guiding characteristics, where the design target of the constructed methodology pertains to waveguide cross-sections. First, the concept of topology optimization and a way to apply it to electromagnetic problems are explained. Design requirements for the waveguide cross-sections are then clarified and corresponding objective functions are formulated. A new multi-objective function is formulated to reduce grayscales since using a penalization parameter for physical property interpolation is ineffective in electromagnetic problems. For the eigen-value analysis, the Finite Element Method with hybrid edge/nodal elements is used, to avoid undesirable nonphysical, spurious solutions. The optimization algorithm is constructed based on these formulations and Sequential Linear Programming. Finally, several design examples of waveguide cross-sections are presented in order to confirm the usefulness of the proposed method.
