Expedited Design Closure of Antennas by Means of Trust-Region-Based Adaptive Response Scaling

In this letter, a reliable procedure for the expedited design optimization of antenna structures by means of trust-region adaptive response scaling (TR-ARS) is proposed. The presented approach exploits two-level electromagnetic (EM) simulation models. A predicted high-fidelity model response is obtained by applying nonlinear frequency and amplitude correction to the low-fidelity model. The surrogate created this way is iteratively rebuilt and optimized within the trust region framework. The utilization of the correlations between the EM models of various fidelities allows for significant reduction of the design optimization cost. The main contributions of the work are twofold: 1) the application of an ARS for antenna optimization (in particular, making it work with coarse-discretization EM models as low-fidelity models); and 2) the integration of an ARS with a TR optimization framework. The operation and performance of the algorithm are demonstrated using two antenna designs optimized for several scenarios. A comparative study reveals computational benefits of the TR-ARS over direct optimization of the high-fidelity EM model. The reliability of the optimization process is further confirmed by an experimental validation of the fabricated antenna prototypes.