In this letter, a structure of a small ultra-wideband (UWB) monopole antenna, its design optimization procedure as well as experimental validation are presented. According to our approach, antenna compactness is achieved by means of a meander line for current path enlargement as well as the two parameterized slits providing additional degrees of freedom that help to ensure good impedance matching. For the sake of reliability, the antenna design process (simultaneous adjustment of multiple geometry parameters) is carried out using high-fidelity EM analyses. Surrogate-based optimization involving an auxiliary coarse-discretization EM model it utilized to accomplish the design in practical timeframe. Penalty function approach allows us to reduce the antenna footprint (to only 15.8 × 22 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) while maintaining acceptable reflection in the UWB frequency range. Experimental validation of the design is also provided.
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