Çizgisel Kaynak ile Odak Dışı Beslenen Bir Parabolik Reflektörden Kırınan Alanlar

Abstract

Bir çizgisel kaynağın bir silindirik parabolik mükemmel elektriksel iletken (MEİ) reflektör antenden kaynaklanan kırınan alanları Geliştirilmiş Fiziksel Optik’in (Modified Theory of Physical Optics; MTPO) saçınım integrali kullanılarak incelenmiştir. Reflektör, çizgisel kaynak tarafından odak-dışı olarak beslenmiştir. Köşe kırınım alanları, Köşe Noktası Metodu (Edge Point Method) kullanılarak asimptotik olarak hesaplanmıştır. Üniform kırınan alanları elde etmede kullanılan hesaplamada Signum (İşaret) ve Fresnel fonksiyonları yardımıyla üniform olmayan durum ortadan kaldırılmıştır. Toplam saçılan, kırınan ve yansıyan alanlar sayısal olarak, parabol genişliği, çizgisel kaynağın konum açısı gibi problemin bazı parametreleri için çizdirilmiştir.

Keywords

• Çizgisek Kaynak
• Parabolik Anten
• Odak-dışı besleme
• Kırınım

Diffracted Fields by a Parabolic Reflector Offset-Fed by a Line Source

Abstract

Fields of a line source diffracted by a cylindrical parabolic Perfectly Electric Conducting (PEC) reflector are investigated by employing the scattering integral of the Modified Theory of Physical Optics (MTPO). The reflector that is symmetrically located with respect to x-axis is offset-fed by a line source. The line source is lying parallel to the z-axis and off the focus of the reflector. Diffracted fields are evaluated asymptotically by means of the Edge Point Method. An approximate way of expressing uniform diffracted fields is used by utilizing the Signum and Fresnel functions together to overcome the non-uniform situations. Total scattered, diffracted, and reflected fields are plotted numerically for some parameters such as parabola width and location angle of the line source in the problem.

Keywords

• Line Source
• ParabolicAntenna
• Offset feed
• Diffraction

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