Publications Repository - Gdańsk University of Technology

Numerical optimization of geometry parameters is a critical stage of the design process of compact antennas. It is also challenging because size reduction is constrained by the necessity of fulfilling imposed electrical performance requirements. Furthermore, full‐wave electromagnetic (EM) analysis needs to be used for reliable performance evaluation of the antenna structure, which is computationally expensive. In this paper, an improved procedure for optimization‐driven design miniaturization of antenna structures is considered. We investigate the properties of explicit formulation with the footprint area minimization being a primary design objective and a penalty function introduced to control reflection characteristic of the antenna at hand. Deficiencies of this approach are pointed out, in particular, difficulties in exploring the boundary of the feasible part of the design space (otherwise necessary due to the fact that the reflection constraint is normally active at the minimum size antenna design). A novel formulation with adaptive adjustment of the maximum acceptable in‐band reflection level threshold is proposed and demonstrated to be superior over the conventional (fixed threshold) setup, ie, leading to smaller footprints without degrading electrical performance parameters. Our considerations are illustrated using 2 broadband antenna structures.

Authors

• David Johanesson,
• prof. dr inż. Sławomir Kozieł link open in new tab ,
• dr hab. inż. Adrian Bekasiewicz link open in new tab