Repozytorium publikacji - Politechnika Gdańska

Over the recent years, utilization of numerical optimization techniques has become ubiquitous in the design of high-frequency systems, including microwave passive components. The primary reason is that the circuits become increasingly complex to meet ever growing performance demands concerning their electrical performance, additional functionalities, as well as miniaturization. Nonetheless, as reliable evaluation of microwave device characteristics requires full-wave electromagnetic (EM) analysis, optimization procedures tend to be computationally expensive, to the extent of being prohibitive when using conventional algorithms. Accelerating EM-driven optimization is therefore a matter of practical necessity. This paper proposes a novel approach to reduced-cost gradient-based parameter tuning of passive microwave circuits with numerical derivatives. Our technique is based on restricting the finite-differentiation (FD)-based sensitivity updates to a small set of principal directions, identified as having the most significant effect on the circuit responses over the frequency bands of interest. The principal directions are found in the form of an orthonormal basis, using an auxiliary optimization process repeated before each iteration of the optimization algorithm. Extensive verification experiments conducted using a com-pact branch-line coupler and a dual-band power divider demonstrate up to fifty percent speedup obtained over the reference algorithm (using full FD sensitivity updates), as well as a considerable improvement over several accelerated algorithms. The computational savings are obtained with negligible degradation of the design quality.

Autorzy

• prof. dr inż. Sławomir Kozieł link otwiera się w nowej karcie ,
• dr hab. inż. Anna Pietrenko-Dąbrowska link otwiera się w nowej karcie ,
• Leifur Leifsson