Modeling and Characterization of a Compact Decagonal Fractal‐Ring UWB Monopole Antenna for IoT, Wi‐MAX, and Short‐Range Sensing Applications Within Sub‐6 GHz to the Lower X‐Band Spectrum

ABSTRACT

This article presents a compact UWB monopole antenna based on a decagonal ring, in which a set of fractal‐inspired slots is introduced to broaden the operating bandwidth while maintaining a compact structure. These slots are added primarily to increase the electrical path without increasing the overall radiator size, thereby making the antenna easy to integrate when space is limited. A prototype is fabricated on a standard FR4 substrate with dimensions of 40 × 30 × 1.6 mm ³ . The proposed design is first optimized using full‐wave simulations and then experimentally tested. The antenna operates continuously from 2 GHz up to 11.20 GHz, with a peak gain of about 5.5 dBi and a radiation efficiency close to 95.6%. Simulated and measured results show a satisfactory agreement over the whole operating range. Besides the wide frequency span, the antenna also maintains stable radiation patterns and satisfactory time‐domain behavior, often challenging to obtain in compact UWB designs. Its compact footprint and simple fabrication make easy integration into different wireless systems. Owing to its compact, optimized design, wideband performance, excellent time and frequency domain characteristics, low cost, and ease of fabrication, the proposed antenna can therefore be used in IoT nodes, low‐power wireless connections, Wi‐MAX system, and several UWB sensing scenarios operating in Sub‐6 GHz, C‐band, and parts of the lower X‐band spectrum.