@article{article_1892221, title={RING NUMBER SATURATION IN NEAR-FIELD FOCUSING RLSA ANTENNAS: A FULL-WAVE PARAMETRIC STUDY FROM 1 TO 10 RINGS}, journal={Mühendislik Bilimleri ve Tasarım Dergisi}, volume={14}, pages={386–398}, year={2026}, DOI={10.21923/jesd.1892221}, url={https://izlik.org/JA86GN86LZ}, author={Satılmış, Gökhan}, keywords={Radyal Hat Yarık Anten Dizisi, Yakın Alan Odaklama, Sonlu Elemanlar Simülasyonu, Halka Sayısı Etkileri}, abstract={Radial line slot array (RLSA) antennas are widely used for near-field focusing, yet the impact of ring count on matching and focal quality remains unquantified. This study systematically varies the number of concentric slot rings from 1 to 10 in a near-field focusing RLSA, using a validated full-wave finite element method (FEM) framework with a wideband 10–20 GHz characterization. The central finding is a saturation point: near-field focusing quality and matched power efficiency improve noticeably up to 6–8 rings, beyond which gains diminish or vanish. Specifically, the matched focusing gain density radiated power per unit aperture area with impedance matched peaks at Ring 5, absolute focal field strength peaks at Ring 9, and Ring 10 adds no significant benefit over Ring 9 in any metric. Radiated power is non-monotonic, dropping from 0.97 W (R8) to 0.88 W (R9) due to radial wave decay in the cavity. These results break the perception that more rings always yield better performance and provide quantitative design guidance: for power-efficient near-field systems, 4–6 rings suffice; for maximum focal intensity, 8–9 rings are optimal}, number={2}, organization={TUBITAK}