Rapid design of microstrip antenna arrays by means of surrogate-based optimisation

A technique for rapid simulation driven design of planar microstrip antenna arrays is introduced. It exploits the surrogate-based optimisation paradigm and variable-fidelity electromagnetic (EM) simulations. The design process includes radiation pattern optimisation and matching. Two low-fidelity models are utilised: a coarse-mesh EM model of the entire array and a model of the array based on the simulated single element radiation response combined with the array factor. Both models, after suitable correction, guide the optimisation process towards the optimum of the antenna array high-fidelity model. Design optimisation of a 5 x 5 and 7 x 7 microstrip antenna arrays is conducted and described to demonstrate operation as well as efficiency of the proposed technique. The computational cost of optimised designs is equivalent to a few high-fidelity simulations of the entire array despite a large number of design variables.