Performance Evaluation of Koch Shaped Antenna for Compact and Multi-Band Applications

In this work, a compact Koch-shaped fractal antenna is designed, simulated, and experimentally validated for multi-band wireless communication in the 1–10 GHz spectrum. By leveraging the recursive space-filling property of the Koch geometry, the antenna achieves significant miniaturization while maintaining strong electromagnetic performance. The proposed design exhibits resonances at 2.46, 3.95, 6.20, 7.34, 9.15, and 9.42 GHz, effectively covering multiple wireless standards such as Wi-Fi (2.4/5 GHz), Bluetooth, ISM bands, and sub-6 GHz 5G channels. The antenna achieves return loss values below –10 dB at all resonant frequencies, with a measured bandwidth exceeding 6 GHz and a consistent gain between 3.2–4.0 dBi. The E-field analysis confirms improved surface current distribution with successive fractal iterations, while group delay studies demonstrate enhanced phase stability. Experimental validation of S₁₁ using a vector network analyzer shows strong agreement with simulations, confirming the practical feasibility of the design. Compared with reported fractal antennas, the proposed design demonstrates superior multiband support, higher bandwidth, and compact dimensions (30 × 30 mm²), making it highly suitable for integration into IoT devices, wearable electronics, radar platforms, and next-generation wireless communication systems.