Yihune, Tekalegn MezemrTekalegn MezemrYihuneUllrick, ThijsThijsUllrickDhaene, TomTomDhaenePeumans, DriesDriesPeumansSpina, DomenicoDomenicoSpina2026-04-222026-04-2220262771-957Xhttps://imec-publications.be/handle/20.500.12860/59153This work presents a novel composite Gaussian process (GP) model for representing the complex-valued scattering parameters (S-parameters) of electrically long microwave interconnects as a function of frequency. The proposed model integrates a rational Szegö kernel, which captures the holomorphic structure and Hermitian symmetry of S-parameters, with a delay-informed periodic kernel designed to capture oscillatory behavior induced by wave propagation, thus resulting in improved predictive accuracy.engJournal article10.1109/lmwt.2025.3629238WOS:0016165784000012771-9588