Isogeometric Shape Optimization of Multi-Tapered Coaxial Baluns Simulated by an Integral Equation Method

Abstract

We discuss the advantages of a spline-based freeform shape optimization approach using the example of a multi-tapered coaxial balun connected to a spiral antenna. The underlying simulation model is given in terms of a recently proposed isogeometric integral equation formulation, which can be interpreted as a high-order generalization of the partial element equivalent circuit method. We demonstrate a significant improvement in the optimized design, i.e., a reduction in the magnitude of the scattering parameter over a wide frequency range.

Figures (5)

• Figure 1: Parameter (left), shape (middle) and topology optimization (right).
• Figure 2: An exemplary spline curve with kinks at $x=1/3$ and $x=2/3$.
• Figure 3: Visualization of balun with attached spiral antenna with tapers based on the design of McParland_2022aa.
• Figure 4: Visualization of the optimized balun design.
• Figure 5: Magnitudes of scattering parameter for original and optimized geometry using $N_\omega=200$ frequency samples.