M. Orhan ÖZYALÇIN, Ercan TOPUZ, Levent SEVGİ

İletim Hattı Matrisi yöntemi ile ekranlama etkinliği ve özgül soğurma oranı hesabı

İletim Hattı Matrisi (İHM) yöntemi günümüzde sıkça kullanılmaya başlanan zaman-domeni tekniklerden birisidir. Bu çalışmada, söz konusu teknik öncelikle analitik çözümleri mevcut olan problemlere uygulanarak kalibre edilmiş ve geçerliliği gösterilmiş, analitik çözümün henüz mevcut olmadığı problemlerde ise diğer bir zaman-domeni yöntemi olan Zamanda Sonlu Farklar (ZSF) yöntemi ile karşılaştırılmıştır. Ele alınan iki önemli problem, ekranlama etkinliği (EE) ve özgül soğurma oranı (ÖSO)'dır. Bu problemlerin ortaya çıktığı yapıların modellenmeleri hayli karmaşık ve zor olduğu gibi bu büyüklüklerin deneysel olarak belirlenmesi de çoğu kez olanaksızdır. Bu nedenle her iki problemin çözümünde de sayısal yöntemler en yaygın ve etkili yaklaşımı oluşturmaktadır.

Calculation of shielding effectiveness and specific absorption rate via Transmission Line Matrix method

Transmission Line Matrix (TLM) method is a very effective time-domain method, which has been extensively used in the past two decades for solving various electromagnetic (EM) problems. This method is not only used in the solution of EM problems but also in that of different types of problems such as diffusion and viscosity in the literature because of its nature. In this work, TLM is applied for determining solutions of two complex EM problems which have not been addressed via TLM. These two problems are the calculation of shielding effectiveness (SE) and specific absorption rate (SAR), which are very important in the daily life. These two areas present difficult modeling and simulation problems which may require excessive computer resources. However, since the determination of SE and particularly of SAR experimentally via measurements is often not possible numerical techniques play a dominant role in such applications. Analytical verification of the results have also been performed by comparing Green 's function solution of a PEC resonator with TLM results. And also radiation from an aperture is used for the same purpose in this study. Very satisfactory results are obtained via these validations. These results have shown that TLM method can safely been applied for solving two complex problems which are calculation of SE and SAR.

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