Accelerated optimization of input characteristics of wideband antennas using improved trust-region gradient search

摘要

Simulation-driven design of antenna structures is a time consuming process due to a large number of EM analyses required by the optimization algorithms to converge. Computational speedup can be achieved by means of various methods including utilization of adjoint sensitivities, variable-fidelity simulations, controlling design space dimensionality, as well as surrogate-assisted procedures. The paper proposes a simple modification of a trust-region gradient-based algorithm with numerical derivatives for optimization of input characteristics of antennas. In our approach, the time savings are obtained by adaptive handling of the antenna response Jacobian updates, based on the design change during each algorithm iteration as compared to the trust region size. It is demonstrated that the proposed algorithm modification may lead to up to 52 percent savings over the reference algorithm with only minor degradation of the design quality. Our considerations are illustrated using three UWB antenna structures.