Topology Optimization of Sub-Wavelength Antennas

We propose a topology optimization strategy for the systematic design of a three-dimensional (3D), conductor-based sub-wavelength antenna. The post-processed finite-element (FE) models of the optimized structure are shown to be self-resonant, efficient and exhibit distorted omnidirectional, elliptically polarized far-field radiation patterns. The computed approximate Q value for this antenna is Q_Z(ω₀)≈ 7.74 for ω₀=2π × 350.8 MHz and it is 1.64 times larger than the theoretical lower bound value.