EKDZ Modelinin Çoklu Kırınım İçeren bir Senaryoya Uygulanması

Bu çalışmada, karasal yayıncılıkta kapsama alanı hesabında kullanılmak üzere ışın izleme tekniğine dayanan yayılım modelleri karşılaştırılmaktadır. Geometrik Kırınım Teorisi (GKT), Eğim Kırınımı ve Dışbükey Zarf Tekniğine dayalı Eğim Kırınımı (EKDZ) karşılaştırılmaktadır. EKDZ modeli hesaplama süresi ve bağıl yol kaybını hesaplamadaki kesinliği açısından optimum bir modeldir. Bu çalışmada 1800 MHz işlem frekansı için verici yüksekliğinin, alıcı üzerindeki bağıl yol kaybına etkisi tartışılmaktadır. Verici yüksekliği azaldıkça binalar daha fazla birbirinin geçiş bölgesine gireceğinden bağıl yol kaybı azalmaktadır. Bu durumda alıcıya direkt gelen ışınların etkisi azalmaktadır

Application of S-UTD-CH Model into Multiple Diffraction Scenarios

In this study, propagation prediction models based on ray tracing in coverage estimation for digital broadcasting systems are compared. Geometrical Theory of Diffraction (GTD), Slope Diffraction (S-UTD) and Slope UTD with Convex Hull (SUTD-CH) models are compared for computation time and propagation path loss. S-UTD-CH model is optimum model with respect to computation time and relative path loss. In this study, effects of transmitter height to relative path loss at the receiver for 1800 MHz operational frequency are discussed. As the transmitter height decreases, buildings penetrate into transition zone of previous buildings and so relative path loss at the receiver decreases. In this case, effects of direct rays decreases

Keywords:

S-UTD-CH model, slope diffraction, radio broadcasting GTD model, propagation models,

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