A Structure and Simulation-Driven Design of Compact CPW-Fed UWB Antenna

In this letter, a structure of a miniaturized ultrawideband (UWB) coplanar waveguide (CPW)-fed antenna and its design procedure are presented. The antenna is a modified version of the design previously proposed in the literature, with additional degrees of freedom introduced in order to improve the structure flexibility. The small size is achieved by executing a rigorous optimization procedure that consists of two stages: 1) smart random search carried out at the level of coarse-mesh electromagnetic (EM) simulation model that aims at finding an initial design featuring small size and reasonable return loss, and 2) surrogate-assisted optimization exploiting variable-fidelity EM simulations and response correction techniques for expedited design tuning. The final design exhibits return loss below - 13.2 dB in the entire UWB band and a small size of 418 mm2. Simulation results are supported by physical measurements of the fabricated antenna prototype.