Low-cost design of SIW cavity antennas using surrogate-based optimization

A methodology for low-cost simulation-driven design of a substrate integrated waveguide (SIW) cavity antennas is presented. Our approach exploits variable-fidelity electromagnetic (EM) models of the antenna structure of interest, response surface approximations and frequency scaling. Coarse-discretization EM simulation data is used as a low-fidelity model, which - upon optimization - provides a reasonable approximation of the optimum design. The design is further refined by means of suitably corrected response surface model constructed again from coarse-discretization simulation data. The entire design process requires just a few evaluations of the original, high-fidelity EM antenna model. Our considerations are illustrated using a specific example of a SIW cavity antenna with total design cost corresponding to about 6 evaluations of the high-fidelity model.