YAKIN ALAN ODAKLAMALI RADYAL HAT YARIK ANTEN DİZİLERİNDE HALKA SAYISI DOYGUNLUĞU: 1 İLA 10 HALKA SAYISI ARALIĞINDA TAM DALGA PARAMETRİK ÇALIŞMA

Abstract

Radyal Hat Yarık Anten Dizileri (RHYAD), yakın alan odaklama için yaygın olarak kullanılmaktadır; ancak halka sayısının empedans uyumuna ve yakın alan odaklanma kalitesi üzerindeki etkisi nicel olarak belirlenmemiştir. Bu çalışmada, geniş bantlı 10–20 GHz frekans bandında, tam dalga sonlu elemanlar yöntemi simülasyonu kullanarak RHYAD’da eş merkezli yarık halkalarının sayısını parametrik olarak 1’den 10’a kadar sistematik olarak değiştirilmiş ve her bir geometrinin analizi gerçekleştirilmiştir. Temel bulgu halka sayısına göre doygunluk noktasının oluşmasıdır: yakın alan odaklama kalitesi ve empedans uyumlu güç verimliliği 6–8 halkaya kadar belirgin şekilde artar, bunun ötesinde kazançlar azalır veya ortadan kalkar. Spesifik olarak, empedans uyumlu odaklama kazanç yoğunluğu birim açıklık alanı başına yayılan güç, Halka 5'te zirveye ulaşır; mutlak odak alan gücü Halka 9'da zirveye ulaşır ve Halka 10, hiçbir ölçütte Halka 9'a göre önemli bir fayda sağlamaz. Yayılan güç sabit değildir; boşluktaki radyal dalga zayıflaması nedeniyle 0,97 W (R8) değerinden 0,88 W (R9) değerine düşer. Bu sonuçlar, daha fazla halkanın her zaman daha iyi performans sağladığı algısını yıkar ve nicel tasarım rehberliği sağlar: güç verimli yakın alan sistemleri için 4–6 halka yeterlidir; maksimum odak yoğunluğu için 8–9 halka en uygunudur.

Keywords

• Radyal Hat Yarık Anten Dizisi
• Yakın Alan Odaklama
• Sonlu Elemanlar Simülasyonu
• Halka Sayısı Etkileri

Supporting Institution

TUBITAK

Project Number

1059B192400146

Ethical Statement

Yazarlar tarafından herhangi bir çıkar çatışması beyan edilmemiştir.

Thanks

Radyal Yarık Anten Dizisi konusunu tanıttığı için Prof. Dr. Mauro Ettorre'yi teşekkür etmek istiyorum.

RING NUMBER SATURATION IN NEAR-FIELD FOCUSING RLSA ANTENNAS: A FULL-WAVE PARAMETRIC STUDY FROM 1 TO 10 RINGS

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

Keywords

• Radial Line Slot Array
• Near-Field Focusing
• Finite Element Method Simulation
• Ring Number Effects

Supporting Institution

TUBITAK

Project Number

1059B192400146

Ethical Statement

No conflict of interest was declared by the authors.

Thanks

I would like to thank Prof. Dr. Mauro Ettorre for introducing RLSA topic.

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