Calculation of Scattered Fields from the Circular Aperture on an Opaque Surface

Öz

In this study, using the Boundary Diffraction Wave Theory approach, the calculation of scattered fields from the circular aperture on an opaque surface was analyzed. Initially, the symbolic expression of the vector potential introduced by Miyamoto and Wolf was used in the BDW Theory integral. This expression was applied to the problem and the non-uniform field expression found was made uniform with the help of the asymptotic association of the Fresnel function, using the Detour parameter. With the Uniform Theory of BDW Umul Y.Z.’s which examines this problem for similarly diffracted fields, the results are compared graphically and expanded for scattered fields. As a result, the uniform scattered fields are calculated and the expressions of the field obtained were interpreted by evaluating them with the graphs obtained numerically for different aperture radii and observation distances. Thus, the expressions of uniform scattered field from the circular aperture on an opaque surface was calculated for the first time with the BDW Theory approach.

Anahtar Kelimeler

• Theory of Boundary Diffraction Wave (TBDW)
• Diffracted Field
• Uniform Scattered Field
• Detour Parameter
• Fresnel Function
• Opaque Surface

OPAK BİR YÜZEY ÜZERİNDEKİ DAİRESEL AÇIKLIKTAN SAÇILAN ALANLARIN HESABI

Öz

Bu çalışmada, Sınır Kırınım Dalgası Teorisi (SKDT) yaklaşımı kullanılarak opak bir yüzey üzerindeki dairesel açıklıktan saçılan alanların hesabı incelenmiştir. İlk olarak, Miyamoto ve Wolf tarafından ortaya konulan vektör potansiyelinin sembolik ifadesi, SKD Teorisi integralinde kullanılmıştır. Bu ifade probleme uygulanmış, bulunan düzgün olmayan (non-uniform) alan ifadesi Detour parametresi kullanılarak, Fresnel fonksiyonunun asimptotik ilişkilendirmesi yardımıyla düzgün (uniform) hale getirilmiştir. Bu problemi, benzer şekilde kırınan alanlar için inceleyen Umul Y.Z.’nin, SKD'nin Uniform Teorisi ile sonuçlar grafiksel olarak karşılaştırılmış ve saçılan alanlar için genişletilmiştir. Sonuç olarak, saçılan düzgün (uniform) alanlar hesap edilmiş, elde edilen alan ifadeleri, farklı açıklık yarıçapları ve gözlem mesafeleri için grafikler ile değerlendirilerek yorumlanmıştır. Böylece, opak bir yüzey üzerindeki dairesel açıklıktan saçılan düzgün (uniform) alanlar SKD Teorisi yaklaşımı ile ilk kez hesaplanmıştır.

Anahtar Kelimeler

• Sınır Kırınım Dalgası Teorisi (SKDT)
• Kırınan Alan
• Saçılan Düzgün (Uniform) Alan
• Detour Parametresi
• Fresnel Fonksiyonu
• Opak Yüzey

Kaynakça

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