Design of a Compact Ultra-Wideband Bio-Inspired Antenna Based on the Antennal Structure of Allomyrina dichotoma

Grounded in structural biomimetics, this study extracts the multi-segmented tapered geometry from the 10-segmented lamellate antenna of Allomyrina dichotoma and maps it to microwave antenna design. Through biological characterization and parametric modeling, key geometric features—multi-segmented configuration, irregular contour, and bilateral symmetry—were extracted. Along the 2D pathway, a 10 × 10 × 1 mm3 PCB microstrip antenna was designed and fabricated, achieving 111% fractional bandwidth from 4.86 to 17.05 GHz with a peak gain of 2.15 dBi and a radiation efficiency of 67–72% across the operating band, plus two additional bands at 24.76–28.58 GHz and 32.66–37.73 GHz. The multiple resonance valleys on S11 curves and frequency-dependent surface current evolution indicate that multi-mode resonant coupling, perimeter increment, and symmetric aperture efficiency together underpin the ultra-wideband performance. Along the 3D pathway, a dipole antenna replicated via metallic 3D printing attains an electrical length of 0.17λ, with 66% bandwidth and 1.45 dBi gain, confirming the same geometric principle in a shape-preserving form. The 2D route favors planar integration and bandwidth, while the 3D route offers extreme miniaturization. This work provides experimental validation of cross-domain geometric mapping from biology to electromagnetics within structural biomimetics, and offers engineering evidence for the intrinsic versatility of this morphology across physical domains.