YUTUCU KESİK SİLİNDİRİN KENARINDAN KIRINAN ÜNİFORM ALANLARIN SINIR KIRINIM DALGASI TEORİSİ İLE HESABI

Bu çalışmada, Sınır Kırınım Dalgası Teorisi(SKDT) yaklaşımı kullanılarak yutucu kesik silindirin kenarından kırınan üniform alanların hesabı yapılmıştır. İlk olarak silindirik dalga gelişi için vektör potansiyeli ifadesi yeniden elde edilmiştir. Elde edilen vektör potansiyeli ifadesi, gözlem noktasındaki toplam skaler elektrik/manyetik alan dağılımının hesaplanmasında kullanılmıştır. Helmholtz-Kirchoff integrali formunda kullanılan alan ifadesi Stokes teoremi ile kırınan alan ve geometrik optik alanın toplamı formuna dönüştürülmüştür. Elde edilen kırınan alan ifadesi üniform olmayan formda sonuç vermektedir. Üniform olmayan alan ifadesi fresnel fonksiyonu yardımıyla üniform hale getirilmiştir. Böylece yutucu kesik silindirin kenarından kırınan uniform alan ifadesi SKDT yaklaşımı ile ilk kez hesaplanmıştır. Son olarak toplam saçılan alan ifadesi kırınan ve geometrik optik alanların toplamı şeklinde hesaplanmıştır. Elde edilen üniform ve üniform olmayan kırınan alan ifadeleri ile toplam saçılan alan ifadesi sayısal olarak değerlendirilmiş ve davranışları incelenmiştir.

CALCULATION OF THE DIFFRACTED WAVES FROM THE EDGE OF AN OPAQUE CUT CYLINDER BY THE BOUNDARY DIFFRACTION WAVE THEORY

In this paper the uniform diffracted fields from an opaque cylinder cut surface are studied with the theory of the boundary diffraction wave(BDW). For an incoming cylindrical wave, first the vector potential is refound. The new generated vector potential is used in the calculation of the scalar electric/magnetic field, for the observation point. The field expression is taken in Helmholtz-Kirchoff integral form. By applying the Stokes theorem, the field expression can be written as the sum of the diffracted wave field and the geometrical optic field. The obtained diffracted wave field expression results in a non-uniform structure. The non-uniform field expression is converted to uniform structure by using the fresnel function. In this work the diffracted wave field from the edge of an opaque cut cylinder is calculated with the boundary diffraction wave theory for the first time. Total scattered field is calculated as the sum of the diffracted and the geometrical optic wave fields in this work. Finally the uniform and non-uniform diffracted wave fields and the total scattered field are examined numerically.

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