A Compact Inverted-F Antenna covering 2.4-4.8 GHz and its Miniaturization Driven by Surrogate Model

This paper presents a compact coplanar waveguide-fed inverted-F antenna (IFA) which covers the 2.4~4.8 GHz frequency band. In order to minimize its overall size, we propose to first construct a stochastic surrogate model that quantifying the dependency of the antenna response on those predominant geometric parameters, and then use it as a lightweight engine to drive a genetic algorithm (GA) for the speed-up seeking of the optimum design. It is shown that the proposed approach can further reduce the overall size by 1.35% compared to the initial design while keeping the expected bandwidth between 2.4~4.8 GHz, i.e. 66.7% relative to the central frequency. It is indeed a considerable gain that can hardly be achieved using traditional manual trial-and-error methods. The overall size of the optimized design is 0.66 λ
g
× 0.3 λ
g
.